Update, unreal seems to be VERY confused about the resolution to output.
This is standalone, used r.SetRes 1920x1080f and that showed me that the resolution was lowered(for no reason! output log was LYING).
This is perf with max motion blur+TAA+native 1080p and optimized settings.
55-60fps from a large angle on a desktop 3060.
This performance is only achievable if the scene is empty, if shadow maps take a caching hit, ka-boom/49fps.