I’ve been a part of a lot of online communities going back 20 years. The fediverse had the most off-putting user base of any I’ve experienced so far. I liked the whole decentralized idea, but the users and culture drove me away.
As for fediverse a lot of depends on the server you chose, for example https://beehaw.org is much friendlier.
Though you can subscribe to different communities and customize your experience, often what you can experience from specific community depends on which server it is located.
https://programming.dev/ and https://lemmy.dbzer0.com/ might be good for technology related communities.