This is precisely what I mean. You and I know that, but the average user might not, and so they would be less likely to discover similar/interesting communities on other instances, especially if they have their account on a relatively small instance, and would not even know to look for them elsewhere. Your explanation here, exactly as you've written it, would be helpful to people new to the Fediverse. If slrpnk.net won't use Lemmy Federate, then perhaps posting this explanation somewhere would let people know that "this is not all that there is" available to them.