You will never ever get decent 1% lows in most titles, the software stack is architecturally fucked in the popular engines and can’t do it. You would need a CPU that’s literally 100x faster than today’s top models for it to be able to compile shaders on-demand within a single frame without hitching. (Or maybe it’s more accurate to say that there’s a massive gulf between what the hardware/drivers need - compiled pipeline objects built/known ahead of time - versus what game engines are doing, building pipelines on the fly on demand, surfacing new permutations frame-by-frame)

When getting rid of actual performance bottlenecks is too hard or costs too much, just make something up.

XeSS is actually pretty great, played Talos Principle 2, a UE5 game on the Steam Deck at 800p 30fps thanks to XeSS.