Are those instances you federate with?
Peter1986C
I am not sure whether it works for communities you have yet to subscribe to, but below everything else there is the second button on the left (with those horizontal bars). It leads to a list of communities you are subscribed to, and is "topped" by a search field.
Most of the more general instances have a science community or something very similar. The only "split" Beehaw has thus far is having social sciences generally be placed inside Humanities.
I do not think a fork of Lemmy would necessarily break AP federation with your instance. Heck, we even have Mastodon and Friendica accounts post and reply here. Eventually smartphone apps like Jerboa would stop working if the codebase would deviate too much, though (unless app devs start supporting both Lemmy and the fork).
Regarding your application, I am reading a lot of stuff about Reddit (and you on Reddit) in your post and maybe that was not the kind of answer the team behind Beehaw was looking for. No offense intended, BTW.
Which means I do not see enough reason for this protest.
Friet. En zoals een ander al aangaf is dat ook handiger in Vlaanderen.
Does the ban not just apply to new cars?
Because of the social aspects it may be more like Instagram than like Imgur, but there is Pixelfed.
I recommend trying to search the full link (while being logged in with a browser, not Jerboa) into search instead of @---@***.&&& because unless the there are others on your instance already subscribed it is not always going to work that way. I hope this is helful to you.
Although to be technically correct, they use Soapbox instead of Mastodon.
I joined it when the calckey.social server was less than a month old. I am definitely staying on board for the forseeable future.