yeah, what we'd really need is issuing ActivityPub Move
events for community actors (afaik both Lemmy users and communities are actors on the ActivityPub side, thus communities can be followed / posted to from Mastodon, too). this would allow moving communities between servers to make sure that followers of the old community just carry on following the new community
I guess moving followers of users would behave in a similar way, albeit probably much less critical for the health of communities
language is full of idiosyncrasies like this (my favorite is an ekename -> a nekename -> a nickname. see Wikipedia). it's perfectly conceivable that should have would be fully re-analyzed in speech like that, so the proper form of the verb to have would become of after should