If they were designed to run at 30fps with this old clunker CPU that's in the PS4/Pro I don't think it'd be too much of a stretch to get these games to hit 60fps with a new CPU that's far more capable along with a much stronger GPU. I'm not talking about rebuilding the games just taking the existing ones and giving them enhancements. There could be some issues with how the compatibility works so you could be right, you never know I get why 60fps isn't possible on the Pro or One X when upgrading games from the standard consoles because those CPU's are just faster versions of what's already in the base consoles but the PS5 is supposed to be using a custom Ryzen.
It's not possible because some of these games can't run at 4k/60 on a PC with a 1080Ti (which is more powerful than the 1080).
Kingdom Come - forget it
Wolf 2 - nope
AC:O - nope
FC5 - no
Evil Within 2 - no
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