So others have already talked about how great Star Trek is. I agree with them, but I think that literally everyone has missed the point of your question:
It's its own lemmy instance. It was spawned from the migration away from reddit, and it's stayed alive since. So combine an active former-reddit community with lemmy and a good reason to all rally around, and finally the final ingredient of federation, and the Star Trek related rooms will always be on every server, and they'll always be populated.