I think November 2019, at that point the PS4 will be six years old, PS4 Pro will be three years and they will be able to have another reasonable upgrade over the Pro and a big improvement over the base PS4. I expect them to keep the mid gen console plan and release a PS5 Pro in 2022.

The PS4 will still be selling but it will have passed it's peak year and be in decline. I don't think Sony will want to hang on to the PS4 for too long as their primary console, though it will be supported for some time to come as is usual for Playstation consoles. I don't expect PS4 Pro to be used as an entry level PS5 with forwards compatibility, since Sony have said they plan to have clean breaks between generations, or for there to be two PS5 SKUs (a base and pro model) at launch.

It's possible that they could delay until November 2020 if PS4 is still too strong to replace but I can't imagine they'd wait any longer. I don't think it's unreasonable to think Microsoft are targeting 2019 as well for their next console, the Xbox One X will probably just serve as an entry level Xbox Two (they have stated they prefer the idea of iterative console releases with forwards and backwards compatibility) and they probably don't want Sony to steal all the hype of having the only "next gen console" for a year or more.

Are you saying that the One X uses all of it's 12GB of RAM for games?

Also, 8 GB of RAM could open up ALOT of necessary possibilities that would be required for 4K (ish) elements for the PS5's OS. 8/8 sounds gravy to me, but I don't follow hardware as closely as you do so I might be underselling the value of 32GB. I just don't think the PS5 needs 32GB of RAM, I think that sort of mentality stems from PC ownership. Just because it's necessary for PC gaming, doesn't mean it is for next gen Consoles.

I would never make such a ludicrous assertion.

Fact of the matter is... The Xbox One X has 9GB for games and still doesn't reliably hit 4k.

It has 3GB for the OS/Background tasks but restricts it's UI to a paltry 1080P.
Microsoft was originally going to have a 4k UI with 4GB.

I never said it needs 32GB. It could have less. It could have more.

And you are right, just because it's a necessity on PC doesn't mean it is a necessity for a console... However.
Consoles tend to choose hardware that aligns itself to the PC mid-range/mainstream because that is where the best price/performance ratios are found.

If the PC is offering 32GB of TOTAL memory (System and GPU) in the mid-range/mainstream then it goes without saying that consoles would adopt a similar amount.
And DRAM densities are increasing, which means more Ram for the same amount of chips/cost.

Next gen is still years away don't forget, time is our friend here.

16gb won't be enough RAM unless they release two models, a basic one and a pro again

Not enough RAM for what? Games? 4K? Internet...? 8GB for games on the PS5 would be double what the PS4/Pro has right now. Maybe they'll prioritize 12GB for games, but I doubt they will cuz that'd mean only 4GB would be for the OS. I don't think 'native' 4K is on Sony's agenda for the PS5, just better checkerboard 4K rendering. Hence why I don't think Sony will have 32GB of RAM for it's PS5. I just don't see it, no matter which direction I look at it from. There isn't a single piece of hardware besides PC's & Laptops that has that amount of RAM - why the hell would Sony and Microsoft jump on that empty bandwagon? 

The Pro has 5.5 GB for games, as far as I remember. PS4 has 5 atm. This memory is flexible though and can be extended if they manage to slim down the OS even more.

I think anyone who expects PS4 to have more than 24 GB is delusional. I’d even assume 16 could be enough for true 4K gaming.

Then what is the point of PS5? 

I would much rather have a PS4 Premium that offers PS4/XBO level games at full 4K, than a PS5 that offers 1440p or checkerboard 4K. 

To me PS5 needs to offer both Native 4K and an undeniable leap in game design. Anything else is just a fancy PS4 with a pseudo PS5 name plate.

It would make much more sense to release a PS4 Premium in 2019 with 16GB of RAM, 10TFLOP/s GPU, and Jaguar pushed to ~3.0GHz with customizations that can enhance the Premium code.

Then let PS5 deliver a full next gen expereince in 2022, giving us 64 - 128GB of RAM, 20+ TFLOP/s GPU, an Extreamly refined 16 core Ryzen CPU, and 4 - 8 TB of M.2 NVMe Storage.

There should be no rush to get out a device called PS5 just for the sake of having a device called PS5. If a new product needs to hit the market in 2019, then a Native 4K PS4 Premium is a much better option, because the tech for a device worthy of the PS5 title, and setting a new baseline for games of the next decade, is just not going to be feasible. 16 - 24GB is not enough RAM to set the tone for next gen, even 32GB is much too small. 64GB is the absolute minimum PS5 should get, and even at that it will be one of the smallest generation to generation leaps we have seen. We also can not have another generation based around mechanical storage. Launching a next gen in 2019 or 2020 with HHD or SSHD would be suicide for Sony and Microsoft when SSD tech will become much cheaper per TB by the mid 2020's. M.2 MVNe prices are falling fast, and it needs to be the standard which games are developed to, and that should start with PS5 in 2022.

Sorry but.... Another reiteration when Jaguar is already the weak spot?! Not gonna happen, nor should it.

How do you think those huge RAM amounts should be factored in price wise?! It’s long hit deminishing returns...nor are those huge RAM numbers even needed for 4K gaming. Not even for VR.

I agree that an SSD would be beneficial to counter long loading times with 4K textures and 100GB plus games, but the growing size of games would make a 2TB SSD mandatory. Not gonna happen, for price reasons again.

This all sounds a little bit like a fever dream.

16GB is fine for games built with PS4/XBO in mind, but when you give devs a much high baseline for CPU and GPU, 16GB would be a major bottle neck. 

PS5 should be offering the ability to have much larger worlds, much greater draw distance, many more NPC's, Much higher deatil in NPC's, a generational leap in foliage both detail wise and density, more effects rendered in full 3D, higher resolution reflections, the list goes on and on. 16 - 24GB is not next gen, it is just a beefed up PS4.

 The increase in RAM will also be of huge importance to VR, even more so than 4K. Even in the current 100 Deg FOV headset the image is being magnified massively putting every little deatil on spot. PSVR 2 should see an increase to at least 120 Deg FOV amplifying things even more. There are things being worked on to focus rendering to where we are looking, but we are still going to need texture well above native 4K to deliver prestine clarity. 

Again, we don't need a device called PS5 just to have a device called PS5. We should not be anticipating a PS5 that does absolutely nothing next gen worthy. We have time, PS4, XBO, and Switch are all strong, and this generation still has a lot to offer, even more if a PS4 Premium comes that can deliver current games at 4K. Let PS5 be an incredible next gen device that delivers on every front.  

PS4 Premium with Jaguar should happen, because the rest of the tech is not there. We don't have the GPU, RAM, or Storage to support a Ryzen based console yet, and we won't in 2019. A Ryzen based PS5 in 2019 or 2020, is going to have major bottle necks at every other compnent.

RAM is no where near deminishing returns. The idea that we have reached the limits on RAM has been going on since computers began. Why this is still a debate after decades of history around this topic is beyond me.

Looking at SSD's, yes, price would be a factor in a half assed PS5 in 2019 or 2020, but a real PS5 in 2022, SSD will be well below HDD $/TB. Every SSD manufacturer is projecting SSD to see massive gains in capacity and $/TB over the next decade, with SSD's massively outpacing HDD in both catagories.