Sports subreddits are a notable exception imo. While they might get a bit silly, r/cfb, r/nba, etc. are so much better than Twitter or any other public forum that losing them would be pretty awful.
The F1 subreddit (over a million subs)is one of the absolute worst places on the internet for any kind of discussion. It's totally dominated by The Hive Mind, dissenting opinions are absolutely unwelcome and the top posts on every single post are low-effort jokes, usually jokes that have been told a thousand times before. It's awful.
MotoGP (250k+ subs) is better, but still suffers from similar problems.
V8Supercars is quiet, but the discussion is of a far higher quality.
"Better than twitter" is a low bar to clear.
The exception is subs that lean heavily into over-the-top curation which is also its own special kind of groupthink hell imo.