Did you play the Talos Principle Reawakened? They took a great performing game made with their own engine, re-released it with UE5, and now it performs like doggy doodoo.

I did. Was kind of underwhelmed by the graphics too. Although that may be in line with a remake. Ie, I gave it benefit of the doubt since I don't know how much effort they put into it beyond "making it work".