There is a constant misunderstanding between open communities where the topic is not defined, like a "Reddit community" or a "BlueSky community", or a "Nostr community" and communities where the topic is defined. People join open communities to discuss whatever comes and join topic communities to stay on the topic and focus. Those are two different things. I don't see how topic communities can sustain their scope of discussion without moderation. And sustaining the scope is the whole point of establishing a community so that you can gather like-minded people.