I wonder if it’s because !lemmyworld@lemmy.world sidebar and rules say:

This Community is intended for posts about the Lemmy.world server.

That means announcements from the team, issues you see etc.

There’s so much spam in this community already. People are using it as a catch-all community

thank you! that’s exactly what I was looking for. Was originally testing and added lemmy.world as an allowed instance and was wondering why federation wasn’t working. TYSM!

Yep! I’ve had issue direct searching for kbin communities here and communities from here on kbin though. I think that kbin federates very slowly.

Examples:

https://lemmy.world/c/apple@kbin.social

https://kbin.social/m/apple@lemmy.world

Not sure why carpet in the bathroom gets so much hate. Drying off is as easy as rolling around on the floor.