Element/Matrix is pretty much what you’re looking for if you need self hosted. Could also look into Jabber/XMPP or IRC but Matrix is going to be way more modern and useable.

@[email protected] linked one reddit post while I was searching for this one, so here it is anyway:

https://old.reddit.com/r/RedditAlternatives/comments/13zl7s1/fediversetips_i_do_not_recommend_lemmy_i_have/

And here’s the OG mastodon post from fedi.tips:

https://mstdn.social/@feditips/106835057054633379

Make sure to “Show More” on each post in the thread, including the replies. I thought it was all spamming the same post for a minute, lol.