A few days ago, Beehaw posted an announcement in their Chat community about the challenges of content moderation and the possibility of leaving Lemmy. That post was eventually locked.
Then, about two days ago, Beehaw posted an announcement in their support community that they aren’t confident about the long-term use of Lemmy, due to so-called concerns about Lemmy.
If you currently use Beehaw and want to stay on the federated Lemmy network, consider migrating your account to another instance like lemm.ee.
I’m not sure that’s a property of the fediverse. You’d have that same issue with similarly themed subreddits for example. And 99.99% of subreddits were also dead spaces.
I believe it’s just as simple as the quantity of users, and has nothing to do with federated or not.