Realistically speaking the 3070/3080 will not "decimate" 4k... unless by "decimate" you mean getting 30-60fps at full graphical fidelity with AA and RT enabled in modern titles.
All your posts seem to be aimed at convincing yourself that 4k gaming is not possible at high FPS. This is despite people already enjoying 4K for years, and the current gen (RTX, Radeon VII, RX5700) enabling 4k60 in many titles. Certainly not with all AA/graphics settings in the most demanding games, but it's certainly playable with high FPS in many games out there.
The next gen will absolutely push 4K forward and will let many enjoy 4K > 60fps, heck older games will see 120 FPS for those with 120Hz 4K panels (LG CX for example...).
As for RT - we haven't yet seen RT performance gains for the 3000 series - I'd expect a massive increase as the technology is still in it's infancy. I personally don't care less if 100% of games can't run at 4k 60 with RT on - as there are hardly any RT games out there anyway.
Looking at the PC spec in your signature - that's obviously not gonna handle 4k or 1440P that well, but don't kid yourself into thinking that 4K isn't possible at high FPS. Even with 'some' sacrifices to settings/AA, it will still look way better than any 1080P/1440P alternative.