Having not played 5e in PnP yet (my group is kinda scattered 😮💨) I have to wonder if Performance is not tied to bardic inspiration or other bardic abilities that used to require performing a song to keep up, much like how casters use Concentration, or if it's simply BG3.
Performance is not an "ability" in DnD I'm pretty sure. It's just something you do with an ability check. You can just go to a bar and play a song or whatever, and roll a performance check. I haven't played Bard in BG3, but I assume what you're talking about is an action you perform in the game that's trying to emulate the feeling of tabletop. I wonder if you can do it around people and make money?
Lol I do the same. Went from “what is this? It doesn’t do anything why is this here?” to doing doing it every turn because I’m a god damn bard.
My favorite is that if you get hit the song gets interrupted for the rest of the turn. Like it was actually doing anything to begin with. I guess it makes me want to get some serious revenge.