It’s at the point where it really doesn’t matter if it’s not true 4K honestly, the difference between something like 1600-1800p and 2160p isn’t even that noticeable on a 4K TV. 60fps > native 4K, if you want a game to be a stunning showcase then do 4k30 RT or 1440p 60 RT. I would take 1600-1800p@60 over 4K@>60.
Maybe with all the smart things like SFS and VRS we could hit native “4K” 60 with certain bits of the screen full 4k and the rest rendered lower. It’s going to get very messy in future because of this, some parts of the game could render in full 4K while other parts render in 1440p.