If those got popular, they could just end up facing the same issue as reddit anyway...
Even without that though, the ux soon being better than reddit with Sync for Lemmy and Memmy coming out is more than enough to put this above all the others, including reddit, imo
There's Tildes but they're not federated and have a pretty snobby admin. Deimos was supposed to be handing down good moderator tools like two years ago but I don't know if that ever happened because I gave up on it.
He still has pretty exclusive control of the site, like only he and other admins (are there other admins?) can make new communities/subtildes(?) and only based on admins perceived demand.