That is entirely possible. My setup seems to be in this sweet spot where the normal performance is high enough over the cap AND the framegen gets you enough extra smoothness AND the VRR is able to eat enough miliseconds off the hitches that it is noticeably improved (but crucially not perfect, so if you're more sensitive than me that may also be part of it). Still, even if it doesn't help for everybody it's worth a shot and not covered in the video.

I bet there is something to having to load the world in chunks in the underlying engine and then having to render the chunk all at once in UE5 that makes UE5's struggles even worse. Still, the game was a shadowdrop, you have to assume they could have taken some time to try to figure it out a bit better.

The worst case scenario is that further optimization isn't an option, but... I mean, even if it is related to what people think it's related they should be able to find some way to ease some of the load off. The observation that a lot of the performance hit is related to hardware Lumen alone points that way. Especially since having a faster base framerate does seem related to having smaller hitches. But hey, who's to say? I guess we'll see where they go from here.