.ini tweaks are just a list of options tweakable by a game, often when you change something in a games UI interface, it changes the corresponding .ini file trigger.
And often a games UI settings do not expose those extra options in the .ini file.

And sometimes a game has a command line interface where you can take things even further, such as idtech, CryEngine and Source.

There is actually a sub-group of PC gamers who try to run games on hardware that is below minimum requirements, it's actually a big community.

The entire Oldblivion project (Something I was a part of) was essentially an approach of rewriting The Elder Scrolls: Oblivion shaders in order to be compatible with Shader Model 1.0. - Perfect for a Geforce 3, which is a similar GPU found in the Original Xbox.

We also did a similar thing for Fallout 3.

And another team created "shadershock" which took a similar approach in order to run Bioshock on older shader models.

System requirements are a guideline in order for a developer to remove any "mud" from their hands legally if their game doesn't work on certain hardware sets, that is pretty much it. - In my 25 or more years of PC gaming, not once have I ever referred to a games system requirements.

Who says it has to look and play identical on all platforms?

Battlefield on 7th gen didn't. Multiplayer was very different on PC thanks to larger maps and player counts thanks to the larger amounts of CPU power and Ram... And it looked almost a generation ahead on PC.

Compare Minecraft RTX on PC to the 7th gen consoles, game looks very different, plays very different, the 7th gen consoles even had world size restrictions.

It usually takes a few years before "dialing things down" to slower hardware becomes impossible or extremely difficult, it takes time for developers to come to terms and leverage the various hardware nuances to the fullest extent of a console platform and build/upgrade their game engines to match, being exclusive or not doesn't really change that.

It does mean that if a prior entry to a game used lots of baked assets and the successor used lots of dynamic assets, then when doing a back-port to an older platform there will seem like there is a big regression in visuals compared to other games as the dynamic assets get turned off.

Case in point: Blacks Ops 3 and Dragon Age 3 on Xbox 360, games looked flat with lack of shadowing and lighting giving definition to scenes.

The Switch seems to be handling backports very well, mostly because it's hardware is very efficient for 720P and lower resolutions, mostly thanks to the efficiency of nVidia Maxwell and it's underlying technologies like tiled based rendering and delta colour compression.
Plus it's hardware features are a match and even exceed the Xbox One/Playstation 4 base consoles in a few areas thanks to being a more modern GPU, so for example the base Playstation 4 and Xbox One use shader model 5 and Switch uses shader model 6 for example... So back porting to the Switch is just easy, much easier than a 7th gen device with outdated and inefficient hardware feature sets.

Except in this case they actually said:

"We are also excited for the game to demonstrate the power of PlayStation 5 this holiday. Marvel’s Spider-Man: Miles Morales will show off near-instant loading, ray-tracing, 3D audio and the DualSense controller. We’ve upgraded our characters with 4D scans and improved skin shading for more realistic looking characters and spline-based hair that moves far more naturally. Many of the city’s assets have also been updated to take advantage of the new console. As you experience Miles’s story, you’ll see, hear, and feel things in a whole new way, all thanks to PS5."

I might be wrong here but to me, that sounds like they actually added stuff to already existing assets, not that they built new assets for this version.

Pointing to PC as an example doesn't help his case. SSDs have been a thing on PC for gaming for quite some time. However, they haven't been leveraged properly because devs take 5400rpm mechanical drives into account. Also PC games in general have are pushed as far as they can because they've had to take the base XB1 and base PS4 into account. I don't get the logic of developing beastly hardware like the Series X only to have the base XB1 as an anchor to it's capabilities. The base XB1 has been struggling with current gen games. Sony is going for a clean break with their 1st Party games and this will give them the decided advantage over MS because they don't have to take last gen hardware into account at all. The strength of consoles is high optimization. MS muting that advantage. Developers were shaky on last gen with X1X, PS4 Pro, Base PS4, and Base XB1 games.

I know there's a subgroup who try to run games at lower than the lowest settings, just like there's a huge mod community that try to push the visuals beyond what the developers intended. However, developers didn't officially support those settings as they typically don't want their games to look totally different on different platforms.

As soon as developers decide to build their game for multiple platforms, parity becomes a thing that affects the entire design and ambitions of the project before they even started making it. Unfortunately, that means the ambitions on the far more powerful platform will always be held back because of it.

What I really don't like about that is just how much of computing power is essentially wasted in the pursuit of 4k and 60fps. I'm not saying that 4k doesn't bring better clarity, more detail etc. but imo, the turn to 4k is happening too soon in relation to available computing power. Hell, 1440p has not even become mainstream in the pc space and now we have this 4k "craze" that brings down even the mighty RTX2080 to it's knees with current gen games. It'll massively slow down the pursuit towards better graphical fidelity, as gpu's in both PC and consoles need to push 4 times the amount of pixels.

I mean, imagine what would be possible on Series X if instead of sticking with base Xbox One settings and maxing out resolution, developers could focus on ramping up visuals to a maximum while keeping 1440p or even 1080p as target rendering resolution. With Series X that won't be possible as developers will already be doing that on the 4Tflops Lockhart.

I asked the other guy this but he didn't answer, maybe you know.  How many 1st party games will be held back by the Xbox One hardware for the 1st year? the 2nd year? I think it will be less than 5 games that could be affected and yet they will look and play better on the Series X.  How many 1st party Sony games will be taking full advantage of the PS5 hardware for the 1st year? 2nd year? My guess a very small amount.  The beastly hardware of both consoles will be utilized...period. The 1st year will be a transition period for both consoles and making that transition as smooth and profitable as possible will be the goal of both companies.  

Can still be downgraded.
It's running on the same game engine as the first game... And is a game engine that would even function fine on an Xbox 360... Swapping in higher quality assets doesn't negate the possibility of downgrading those assets later, it actually happens often in game development.

PC games constantly improve every year.

If the Xbox One and Playstation 4 stayed on the market for another 10 years, the console ports will still get more and more enhancements as PC technology continues to progress.

Case in point: Tessellation during 7th gen. Ray Tracing this gen.

Storage speeds are not as much of a hindrance on PC as the PC is also a memory rich environment... A mid-range PC has 3x the total Ram as a Playstation 4 and 50% more than a Playstation 5, more data can be loaded into System and GPU memory in one load rather than streamed in iteratively.

Not really. PC isn't console. PC games generally always look superior to console versions.

Just because those settings aren't exposed in a games User-Interface doesn't mean that developers have hidden those settings behind lock and key, most game engines and games have documentation that provides the appropriate guidance on adjusting settings outside of the games internal user interface. (Some games even have an "app" outside of the game for you to do just this.)

Parity isn't a thing.

Battlefield on Xbox 360/Playstation 3 was severely paired back in map sizes and player counts and graphics. Massively in the graphics department.
Minecraft on Xbox 360/Playstation 3 had limited map sizes and blocks, definitely not parity.

Battlefield 5, Call of Duty: Modern Warefare, Control,  Mechwarrior 5: Mercenaries, Metro Exodus, Shadow of the Tomb Raider, Wolfenstein Young Blood, Doom Eternal, Dying Light 2, Watch Dogs: Legions and allot more... Have this thing called "Hardware Ray Tracing". - The Xbox One and Playstation 4 variants do not, definitely not parity.

Pretty much every PC game since forever can exceed the 3840x2160 limit of the Xbox One X and Playstation 4 Pro. - 7680x1440 or maybe 11,520x2160 tickle your fancy? Again. Not parity.

60fps? Try 240fps. Not parity.

HBAO instead of SSAO? 16x AF rather than 4x? Super Sampling instead of FXAA? No parity there either.

We were in the same position years ago when people complained about how much "computing power" is essentially wasted in pursuit of 1080P.
During the 7th gen people would praise games like Uncharted and Halo 4's visual makeup... But resolution wasn't apparently important then, suddenly 1080P became super important during the 8th gen and anything less was utter garbage.

Resolution is just a piece of the rendering puzzle, 4k is far from a craze, it's an actual standard.

The PC cannot be compared to consoles in this regard, PC displays are generally smaller with higher pixel densities than a television, so 2160P isn't as important.

Hardware has a resolution "efficiency curve".

Cutting back games to 720P on the Xbox Series X would not bring you much additional rendering headroom over say... 1080P, because the bottleneck in the GPU pipeline isn't fillrate.

Eventually 2160P will be in that same situation, 1440P is barely a performance hit over 1080P on a modern and decent GPU.

Microsoft, Sony and Nintendo just simply need to deliver the hardware and the appropriate software stacks... Leave the rest (including resolution) up to the developers.

Of course a high-end pc will always look better than consoles. But you have to admit that there's a big difference between modern pc ports, that were designed around the limitations of consoles, and the AAA pc exclusives we saw in the past and were completely impossible to run on consoles at all. Back in those days being part of the pc master race actually meant something. You had games like BF, Crysis, Half Life 2 etc. that looked 2 generations ahead of anything on consoles, and we were happy if we could run Crysis at all, never mind at 120fps.

We will see with Lockhart and Series X but I find it hard to believe that the games will look any different on both consoles. Instead it'll probably just be like Xbox One S and Xbox One X. They play the exact same games, but the Xone X is the niche version for those who absolutely demand 4k and 60fps. If Lockhart will be half or a 3rd of the price, I'm sure MS knows which one will sell more as we can already see how 4 out of 5 consoles currently sold are the cheaper base models. This is why I feel developers will completely optimize overall visuals and resolution for Lockhart, and Series X will be kinda forced to "waste" those extra Tflops and RAM on just boosting resolution/ framerate and sprinkle in some extra effects.

Imo that's also why the ps5 exclusives will stand out by a mile as they are not constrained by any platform. We will likely see a TLOU3 or GOW2 completely optimized for ps5 while targeting the exact same resolution and framerate as Lockhart. Those would easily be able to push the visuals way beyond what's technically possible on Lockhart. Maybe we won't see those games right at launch, but I wouldn't exactly count out HZW, though. GG are pretty damn good at raising the visual bar and HZW is the perfect ip to flex those next gen muscles.

Lockhart won't be 1/3 of Series X price, not even 1/2.

From the rumour almost everything is the same between both. It have 1/3 of the GPU power and a little less RAM and CPU power that would keep similar performance to Series X on the intended resolution. Probably some saving on cooling as well and perhaps it will be full digital.

The GPU isn't so expensive that cutting its power in 66% would make the price drop the same.

The only way for Lockhart to be half the price is if MS sell Series X for profit (let's say 599) and subside Lockhart discless (for 299).