I watched the recent Xlayna video with passthrough. It's really interesting, unfortunately with Quest 2 cameras the effect isn't very immersive. I can see how it could be really cool in the future.
I wonder if there is a way to match the lighting better. Recently i saw a tool that could take any 2d image and light it from a different direction (Clipdrop Relight). Maybe something like that could be possible for videos too