relevant magazine is /m/RedditMigration here on kbin.social. You can see it's the one and only report in the modlog yet the user who removed the comment is not listed in the moderators list, is not even a kbin.social user, and did not remove a lemmy.ml comment. Yet, it was removed for me as a kbin.social user.
How is this moderation working exactly? It's understandable that lemmy.ml mods can remove things for lemmy users, and mods on a magazine can remove things on the magazine. But it seems this is an unrelated user, removing a post of a user from an unrelated instance from a unrelated magazine.
How is this possible? what's going on here?
Edit: I checked on lemmy.world's copy and the comment is still visible, meaning the removal did not federate to lemmy.world.
With ActivityPub there is no forced actions on other instances. When a delete happens on an instance, it sends a "this was deleted" announcement to the relevant instances it knows about. The servers that receive the message could easily ignore it and keep their copy of the message active/visible.