I play on PC so I’m not sure if this will help you, but you can enter a phrase into the launch options for BG3 on Steam to make it skip the Larian launcher altogether. So if the Larian launcher is the problem, going directly from Steam to the game should cause the game to launch.
I had this exact problem randomly a few months ago, and this fixed it.
The phrase was something like -skip launcher—
Entered into the launch options for the game on Steam
Or —skip launcher-
You may be able to find the exact phrase by googling
Edit: Here it is, this might workhttps://www.reddit.com/r/BaldursGate3/comments/15iqgfb/psa_skip_launcher_on_steam/#