If I understand Lemmy correctly, you can create duplicate communities on different instances. Isn’t this kinda counter productive because this may lead to less user interaction in those communities, because the user base gets split up between competing communities.
Is there a way to fight this division of the (small) userbase or is this effect even desired because it leads to more tight knit communities on the different instances?
The most effective solution is to search for existing communities on federated instances before creating a new one on your instance. Then new communities are ideally only made if the existing community doesn’t meet your particular need or specific interest (eg. UnitedKingdom vs UKCasual), or if your instance doesn’t federate with the main community.
The same dispersion of userbase is present on reddit but the more popular urls/content will eventually become clear and less popular communities will either aggregate into the main one or become more niche (eg r/games vs r/gaming).