Well, this is the gamers opinion:
https://www.youtube.com/watch?v=Fz1oMAMisgE In short: He thinks that we nowadays got almost no native game resolution anymore and that a native resolution is still "the optimum".
I do agree... as long as a hardware is able to run it smoothly, which is not the case anymore on way to many games. I do think that some AI technology such as DLAA (deep learning anti aliasing) is the best quality possible = native combined with AI. However, the thing usually done is to scale up a very low res up to the monitors native resolution... which is basically the main work done by the AI. This is not per se a "image quality enhancer" but a method in order to gain more performance. It is even better "improving" a native res picture instead of improving stuff which is 480P or just a bit higher than this.
Some methods may involve "interpolation" which is adding lag and ghosting, or at least vulnerable to it... and upscaling is in general vulnerable to artifacting. If the game engine is not perfectly tuned for it... i think there are always some "faulty" objects inside a game, although the overall quality can still be great.
RT is in general vulnerable to "grittiness" which could result into a slightly more blurry image. In order to counter it a lot of powerful technology may have to be used... and this means "even more performance demand": RT is, even in the rather far tuture... a very demanding thing.
And this is the industries opinion:
https://www.youtube.com/watch?v=E1EhcFMKoIU In short: Mark Cerny thinks that the traditional rasterization is not increasing a lot anymore and ML (machine learning) combined with upscaling is the future. PSSR is his biggest projekt he ever was part with and indeed... the PS5 Pro in this case is kinda a "Beta platform" for the PS6 and up.
And this is basically "status quo", on a PS5 Pro (which is about mid range compared to PC):
https://www.youtube.com/watch?v=1XYtBP3Tmcs In short: A game like RE4 Remake is running at a resolution a bit above the PS3 = 720 P resolution and then upscaled using PSSR up to 4k.