These servers have appeared to banned and cleared the SPAM accounts, so they are safe to remove limits (Be sure to suspend all the spam accounts before doing so to clear them out).
lovelive-misskey.t1nyb0x.cloud
uma-aji.com
mi.c-at.jp
misskey.shunrin.com
rhythmisskey.games
social.onlinesession.app
catcore.life
The following closed registrations, but haven’t cleaned the SPAM or can't verify.
mk.hoshisaki-h.com
misskey.favskey.online
The following is down:
misskey.akatuki-host.com
dicekey.jp
tickler.cc
nagomisskey.com
These two servers started spamming.
misskey.gfserver.jp
minecraft.bktsk.com
Will provide updates to this list
As it stands, 6 servers are still sending SPAM, three servers are down.
It appears that social.onlinesession.app has cleaned up the SPAM and disabled open registrations, so this server limit can safely be lifted.
This brings down the list of affected servers to 6.
Update, the count is now 7, as catcore.life is affected by SPAM.
Update 2: It seems I missed that one, as that server already cleaned up the SPAM. The count is 6.