The way I see it, the fediverse itself is the conversational arena, not any particular community within the fediverse. Communities limited to a single instance shouldn’t have primacy, because some of those instances don’t even want their communities open to certain other instances on the fediverse. Since some of the biggest communities keep defederating each other over petty moderator politics, it’s absolutely a good thing that the the fediverse has multiple communities for the same topic, or even with the same name. As long as you’re on an instance that doesn’t defederate other instances, you’ll see them all and can interact on them from a single account. More than that though, people wielding too much centralized power always turn out to be dicks, so anything that maintains decentralization of power is good.