No, I think the culprits are the 100% gamers who always expect too much.
They said up to 120hz, and 4k does not mean all games will be, and they are definitely delivering.

The same goes with any announcements, gamers in general are just crazy about what their excepting...

For example: Someone from the Diablo 4 (Rob) was announcing a surprise on Twitter for the day after, (4 days before the release) and people on Reddit were really going crazy and believed that it would be a new surprise class (Paladin). lol I mean, you cannot make this up... At the end if was just a simple promotion... People are just completely crazy with their expectations and then blame the publisher for not delivering what they made up in the first place.

That's a very weird take.

First: Just because they are first-party games does not mean that they can defy physics... The console, while being powerful for a new-gen console (or the most powerful) does not magically make it capable to run all games (esp. the most complex ones) at 4k/120hz, not at all. Starfield for example is using the CPU intensively to give that open word experience where anything can happen (like Fallout, Skyrim etc... which also makes those games so great). Let's not use Redfall as an example, it was def. not a good release and we all know that. But it is def. an exception, not the normal.

Second: Halo Infinite, Forza Horizon, etc... Are actually achieving that. The same goes for Sony with few games, this is just normal. The difference between the Play Station 5 and the Xbox Series X is not that big, why would you expect their games to be that different? I mean if you look at Diablo 4 for instance, it loads FASTER on the Series X... Even if Sony has the better SSD, this is because the Xbox Series X has a better CPU and the decompression is faster. Each console has advantages and disadvantages. But I don't think anyone should expect major differences between the two. Both consoles have the about the same capabilities, one has a more powerful CPU, one has a faster GPU frequency, one has a faster SSD, and one has faster memory access... 

Third: Finding games from Play Station 5 more impressive is definitely entirely subjective; we are talking performance here not artistic/gameplay/story/presentation which is definitely 100% subjective and if you are mainly a Play Station gamer you will find those games genuinely better for you; same goes for me for Xbox games. In general, the performance of both consoles is pretty similar to their first studio games (and Redfall, does not represent ALL first-party games, just so we are clear).

Finally: The price tag is NOT higher. They are the same. They both have a disk reader and come at the same price. If the Series X would have a digital version only, it would probably come at the same price tag too than the Play Station 5 digital.

Like I said, in my previous reply, gamers are expecting things that are not realistic... That's not the fault of Microsoft or Sony.

Overhyping? And what did they supposed to do, underhype it? It's called marketing.

I've certainly been impressed with some games this generation. Ratchet and Clank and Horizon FW looked fantastic and ran well. Upcoming games Starfield and Final Fantasy 7 Rebirth both look incredible. If we get a mid generation upgrade it will probably be closer to what was in gamers heads.

Corporations overhype often in marketing. They have to be way more careful when talking to investors, because they can get in legal trouble.
The 8K support is not really a lie, as a few tiny games support it. I don't think they ever really pushed it as one of the big selling points because it's not feasible. It shouldn't be listed on the boxes, though.
120 FPS is a lot more common, than 8K. So that isn't a lie either.
However, Jim Ryan blatantly lied about "we believe in generations". From the launch of the PS5 to the present, tons of games have been cross-gen. GOW: Ragnarök seems to be the last cross-gen first-party game, as nothing is announced for the rest of the year onward. It's not that there were 1-3 Sony games that were cross-gen that made Ryan's statement a lie. It's that there have been plenty, and at least one is a flagship title. And when I said tons of games are cross-gen, I'm also referring to the mountain of cross-gen third-party games. Even Hogwarts Legacy got eight-gen versions, despite them releasing later. You have to go out of your way to find PS5 titles that aren't on PS4. And while PS5 is more distinct from PS4 than the Xbox One is to the Xbox Series X/S, Ryan still lied.

Im honestly willing to give everyone a break for the delay in this gen truly taking off because of the pandemic. Between console scarcity, workflows being interrupted and chip shortages, it's no wonder we haven't even tapped into the full potential of these machines.

I do think it's both. I get what you're saying that some gamers creates weirdly high expectations like wishing for GTA 6 on a indie direct. Tho I would say mostly the company/dev/creator's side is at fault. The gamer side you're seeing consists of fanboys, haters, and trolls. It doesn't represent the whole. Whereas the company side comes from the person in charge. It's their responsibility to control information. They know what they're doing yet they still proceed, because it's part of the marketing. Just like how Geoff Keighley hypes up his show despite being filled with mid most of the times. Is it the gamer's fault how Todd Howard is constantly lying by omission and sometimes even blatantly wrong. Or Cyberpunk2077 promising us so many things despite not being able to fulfill them. I don't think so. 

Give me an exemple of lying by omission?
This is not a thing based on my experience, it is actually exactly that: people assuming stuff and building expectations and then calling someone a liar because they are not saying what they expected or come up with something that was just not yet decided but became a thing. I do not think this has anything to do with the topic anyway.

For the Summer Show, you are illustrating exactly my point. Perspectives are very different from one to another, for him, he was hyped by those announcements to show that but it looks like for you it was ‘overhyped’, at the end you are the one building up that hype based on your expectations and they are simply not aligned with others.

Same goes for the for fans for both side; I personally have zero interest in Spider-Man (or whatever Marvel/DC stuff) and even less for any games related to this. For me the Spider-Man stuff was definitely not at all important so I could say that he overhyped it? Just cause I did not care? Or Final Fantasy 7 Rebirth? For me it was amazing and really was the top of the show? Why because I love it and I think it was worth the hype… see at the end it is pretty much always the gamers perspective that is very tainted and biased that build this unrealistic hype and expectations.

I can't say I really understand the takes defending the companies by saying it's marketing and pushing the blame unto gamers for expecting too much. Obviously it's good advice in general to be cautious of marketing speak, but it feels a little like saying that it's fine for companies to make misleading claims because you shouldn't believe them. Again not saying anybody outrighed lied in these cases, but I would consider some of the pre launch information misleading.