Take https://lemm.ee/c/moviesandtv for example. From lemmy.ml, lemmy.world, and sh.itjust.works, you can’t see any posts or comments from lemm.ee users, and lemm.ee users can’t see any posts from other instances.
I don’t know what’s broken, but something is badly broken.
Something is definitely wrong. I have noticed I got no interactions with my comments since the upgrade. Which is unusual