Last time that I checked all the features, departments and rendering aspects ending up in a tug of war regarding performance stagnating any GPU performance increase.
Anyone can view what got faster and what got slower here, this is preview but I’m working on updating to “stable” 5.4.
My guess is the GPU performance improvements are extremely conditional(abusing 5.3 for no good reason other than making abusive 5.3 scenarios faster in 5.4). What would improve performance in UE title releases would to be creating better optimization workflows for developers(better LODs algorithms, precomputed hierarchy meshlets, LOD streaming based on a global speed variable).
There is only so much performance they can give us without redoing several designs which I doubt Epic will fund any time soon. They keep iterating on fundamental broken technologies with almost no changes every time. Lumen works the same way, we work with it the same way. Nanite and TSR, again we flip them on and have no options for anything(TSR doesn’t have enough variables to fix it’s fundamental issues).