Maybe you are right, 

I would like to know how PCs manage memory vs this gen consoles. 

Quantum break, Battlefront 2 are asking for 16 GB of ram and 4/3 GB of VRAM. Recommended.

Cod WWII 12 GB of ram and 6 GB. Recommended. 

They run on current premium consoles, but that gives me an idea that if they make a 16 GB of ram console, games are going to stall. I mean, next gen would last for at least 7 more years. Last time they add 16 x more RAM. If they only double it, it would become a bottleneck in the years to come. But it can happen.

They tend to be downgraded experiences on console verses the PC though.
Even the Xbox One X isn't matching the PC's ultra.

We would probably be looking at AMD's next gen GPU architecture by then.

GDDR7 would be amazing. But I doubt JEDEC would have gotten off their ass and ratified the standard by 2020 considering how long we were sitting around with GDDR5.

16GB of VRAM is certainly enough for 4k and high-quality texture. If it was completely dedicated to graphics.
Throw in system memory, OS memory, apps, background tasks and cats... And then 16GB of total Ram starts to look antiquated.

Hmm it's 4 years later now and I lost interest in 4K lol. What does it need for VR at a decent resolution is the question now :)
16GB ram will be plenty as those 4K textures won't be necessary.

Actually for VR we will want even higher resolution textures, because you can zoom in on everything. Muddy low res textures, will be very illusion breaking when the graphical fidelity and resolution is enhanced. 32GB of RAM is the absolute minimum the next gen consoles should have. 24GB for Games, and 8GB for the OS, Multitasking, Apps, Streaming, etc. should be good enough to make TV gaming look a bit prettier, and make a signifcant leap in VR. 

12-14TF, a decent Navi CPU, 32GB of RAM or
24GB of high quality RAM. Am UHD disc drive so games can be 100GB and a 2TF SHHD. Launch price between $400 and $500. Launching during the holiday period of 2020 or 2021. Depending on how low Sony wants the launch price to be.

That may have used to be true in the past but now I'm not so sure anymore since there's nothing stopping their recent momentum. (industry on the verge of transitioning to EUV, Rambus reuniting with JEDEC(!) and higher demand than ever for higher performance DRAM) Before memory standards used to have a much lower turnover rate but currently their bringing out new memory standards faster than they did in the past. GDDR3 standard wasn't developed by JEDEC since they adopted it from ATi Technologies at the time, the specifications for the GDDR4 standard was released in 2006 by JEDEC, GDDR5 standard was released in 2007, GDDR5X standard was released in 2016 and the GDDR6 standard released a year after that. Consequently the original HBM standard was adopted in 2013, HBM 2 standard was finalized in 2016 but HBM 3 standard could get finalized by as early as the end of this year ... 

The final DDR5 standard is about to be published this year too ... 

Yep, edited my post again. It will probably be 8/8 core zen cpu with 2,6 ghz. I'm not certain you're 100% correct but I believe Sony will stick with simple specs for ps5.

I think the PS5 power will be about the same as the XBX

Seems I got the spec with the lowest performance in my Ps5 prediction. I believe I'm right and a lot of people here will be disappointed in ps5.

8/8 core ryzen cpu with 2,6 ghz clock speed (no extra threads), 9 TF navi gpu, 16 gb gddr6 (with 448 GB/s bandwidth) and a 2 TB laptop mechanical hard drive (140 mb/s read speed). These are my specs for Ps5.

Keep in mind power consumption and cost when making the prediction. The Gpu need to draw about 120W and the CPU about 15-20W and the rest about 10W. Otherwise they need more expensive cooling system like the Xbox one X is using and it's very unlikely Sony will go that route.

On 7nm transistor technology it's very unlikely we see a GPU with more than 10 TF because then power consumption will go above 120W, Sony will likely just double the gpu cores (compared to the ps4 pro) with some clock speed increase which give 9 TF. On memory bandwidth I expect sony not to go with the fastest GDDR6 memory speed because of cost and power consumption. And on Cpu a 8/8 Core ryzen with 2,6 Ghz clock speed should pull about 15-20W on 7nm.

I don't expect Sony to do anything fancy with the Ps5, like an additional ddr4 to run the OS, a flash drive to give shorter loading times and more RAM or some kind of HBM+DDR4 combo. This is because of Cost, need to keep it down.

The simple reason is cost. Top tier graphic cards usually cost more than whole, brand new console. Of course they could get a good deal from AMD, but it's more reasonable to think that they'll stick with cheaper and already well tested option. 

In terms of price tag, I seriously doubt that they'll do the same mistake as they did with the PS3. That $400 price is a psychological barrier, regardless the inflation. It turned out pretty well for them with PS4 and I don't see no reason why they wouldn't attempt to repeat it. Bare in mind that this time around MS will be much smarter and more competitive in the field of pricing. XBox One X is targeted towards enthusiasts and I don't see it (or PS4 pro) outselling base PS4 any time soon ... or ever, unless we see some huge price cuts.