The PS5 can do 4K just fine. Graphical fidelity is always a moving target. It will never stand still and allow hardware to catch up. That being said for the prices consumers are willing to spend on home consoles they'll usually struggle to do full 4K 60FPS+ with ray tracing. You can spend $1000 on a PC graphics card and not be able to meet that without DLSS. No way is a $500-$600 console going to come close to that.For last gen the Pro consoles made sense in concept.
People had 4k TVs, with no 4k content
Problem is, PS4 pro couldn’t actually do 4k content.
Now PS5 can’t do 4K content, and they wanna sell another console based on the idea of 4k content