I doubt that this would ever happen. But... If it does, I think it would be a good thing. The reason is that it would finally motivate game developers to be more realistic in their minimum hardware requirements, enabling games to be playable on onboard GPUs. Right now, most recent games (for example, many games built on Unreal Engine 5) are unplayable on onboard GPUs. Game and engine devs simply don't bother anymore…
True. Optimization is completely dead. Long gone are the days of a game being amazing because the devs managed to pull crazy graphics for the current hardware. Nowadays a game is only poorly optimized if it's literally unplayable or laggy, and you're forced to constantly upgrade your hardware with no discernible performance gain otherwise.
I don't think it has ever been the case that this year's AAA games play well on last year's video cards.