> couldn't
More like wouldn't* most of the time.
Well isn't that the case with a few other things? FSR4 on older cards is one example right now. AMD still won't officially support it. I think they will though. Too much negativity around it. Half the posts on r/AMD are people complaining about it.
Because FSR4 is currently slower on RDNA3 due to lack of support of FP8 in hardware, and switching to FP16 makes it almost as slow as native rendering in a lot of cases.
They're working the problem, but slandering them over it isn't going to make it come out any faster.