Keep playing dumb?
FSR4.0 not usable on Pro - it doesn't support fp8
And until ~transformer~ itself can't be implemented on Int8, and there were some tricks with it as some parts of transformers very sensitive to outliers leading to almost mandatory FP usage, Pro was out of luck
And it was not like Sony didn't wanted or didn't send efforts - it's just problem is complex and hardly can be solved fast by efforts of one company. I posted white paper in another thread regarding this problem - it was from 2022 (very new for this type of things). Nvidia, who probably have the most power in upscaling tech, developed int8 transformer just at the end of 2025, not that far away from Sony/AMD
But yeah, ignore details and specifics and stick to "simple and obvious (and wrong" answer
Those are your fantasies
We have some statements indicating that models were developed jointly and FSR4 based on pssr1
And it's understandable as model development is iterative process where the more smart guys you have the better
You just assume that just because Sony didn't use FSR4 outright means that they were behind, completely ignoring fp8 shenanigans those are very important to understand reasoning and flow of events