I'm more impressed by the guy that rewrote chunks of the Mario 64 source to make it run up to 60 fps on real hardware with better graphics and a number of big fixes and qol enhancements.
He did so much with that game, including decompiling the entire game and building modding tools to make it easier to make modifications. An absolute legend in the romhacking community.
You can already do this today with emulation. Looks fine but depends on the game. Games where textures just complement the polys like Mario 64 work pretty well, plus your brain just adjusts to the look if you're having fun otherwise
It's a big enough problem when you plug an n64 into a modern TV, you see the gaps between the polygons that the developers never intended you to see! Given that this is actual new hardware though, I'd hope they're doing something new and clever with how they actually generate the graphics. Hopefully we'll see some demos posted soon!