What they don’t seem to understand is that in the fediverse it’s them who are responsible for curating their own experience, there’s no big content algorithm doing it for them here.
It’s their job to join communities they may like and then set their main page to “subscribed”. They don’t have to keep it set in “ALL” if they don’t want to see content from all the servers their server federates with/isn’t defederated from.
Lemmy and kbin may be discussion platforms/link aggregators, but they aren’t reddit.
Basically, Lemmy communities and Kbin magazines are federated as groups to the micro and macroblogging fediverse. People in friendica, mastodon or Firefish can interact with Lemmy and kbin by mentioning a community/magazine in their posts and following them the way they do with other types of federated groups (like guppe, chirp, friendica forums, etc)
Pixelfed didn’t have federates group support, meaning that its federation with the threadiverse was bad, not to say practically non-existent. Supporting federated groups and even having its own type of group will allow people on pixelfed to interact with Lemmy and Kbin the way other fediverse software do: following them and tagging the community/magazine handle in posts.
short summary: It means better federation between Pixelfed, and Lemmy and Kbin.