Could be (at least fediverse style), but not sure who/what to follow or how to filter out what I mentioned.

Stuff as in anything, intentionally broad there.

Non-commercial is harder to nail down, but by and large I mean not-for-profit, sort of casual hobbyist activity with zero interest in trying to turn it into a business/side-hustle. People discussing/sharing their original stuff simply for its own sake.

Not fan work, coverage of commercial works, etc. Nothing against that stuff, it’s just easily found and readily available.