I am sure we will not see a another crazy evolution or improvement not because the hardware is weak , but the requirement to achieve the goal is close and already achieved. We just need to improve performance, and focusing more on Smart AI for enemies, and NPC. Super fluid animation, crazy fluid weather effect , Seamless world transition and open world with extra detail full of living NPC. Also living , breathing world and super detail physics .
You have to know what the goal is before a proclamation like that can be made and you can't just improve performance without considering cosmetics. It is very much a system of 0s and 1s.
The goal is to achieve photorealistic graphic .which i can say current gen already can do decent job. Game engine like Frostbite engine, Unreal, Capcom Resident Evil Engine with scanning etc already did fantastic job.