

Yes, you need closed source Nvidia drivers. That’s a pretty heavily discussed topic. Basically, it’s because Nvidia refuses to open source their drivers. They’ve started open sourcing some components, which is nice, for sure, but not enough to game on. I buy AMD video cards specifically because they work really well on Linux without any work at all.
I’m surprised you’re seeing issues on Hogwarts Legacy though. My wife and I have been playing it over the last few months on two different machines both with Bazzite and haven’t had any issues at all. We don’t use Nvidia cards, so it might be an issue with Nvidia’s drivers.

I use Valve’s Proton and don’t have this issue. That’s not it.
The parts of Nvidia’s drivers that they’ve released as open source are not enough to game on. You have to add additional code to actually be able to game, whether it’s community drivers or Nvidia’s drivers.