Im joining in on the reddit ditching thing, and was kinda worried at first that i wouldnt be able to like use it the way i did reddit as it feels like a whole new place, but after engaging with posts and people and actually being a part of lemmy rather than being lurk mode all the time i was pleasantly surprised with how easy it is to become a member of the community, theres a reasonable amount of subs (or whatever the other word for em is) that fit my interests, enough linux content and shitposting for my liking, and the overall random posts made by people equally fed up with Leddit. (also i admit i used reddit a little cus there was this post on the fedora sub showing how to fix a sound issue i been having after a recent update)
I think a good example are the /r/gaming and /r/games subreddits.
/r/gaming is a default subreddit so it has a lot of traffic from users (37 million) of all different backgrounds that may not mesh nicely with the actual hardcore gaming community.
/r/games is not a default, users (3 million) need to seek it out. It generally is more civil and encourages good discussions.
Something like this can be done where !gaming@lemmy.ml could have a different user base and feel than !gaming@beehaw.org , or even !gaming@feddit.de which could be specific to the German gaming community.