How is Lemmy dealing with multiple communities on the same topic? - Lemmy.world

I come from Reddit and been enjoying Lemmy so far. How is Lemmy dealing with multiple communities on the same topic? To me: - If the communities are all active, then I shall subscribe to all of them, but end up having lots of duplicate/similar posts on my feed - If there is one community that is dominating, then what is the point of federation? I was subscribed to [email protected], and just because I actively went into it, I saw a post that the community was frozen and they decided to use another android community on a different server, to avoid fragmentation.