No, your canaries are already long dead. It's long been a process when Reddit admins don't want a sub to exist but it isn't actually breaking any rules to laser focus on the moderators, ban them the moment they have an excuse, immediately ban the sub for being unmoderated, refuse to give it to a new mod via reddit request and ban any replacement subs for recreating a banned sub. Hell, r/GamingCircleJerk has been laughing about some right wing gaming memes sub having that done to it just a few weeks ago.

They only care about it not looking like they are just nuking subs they don't like is because they don't want to scare off other users who might get antsy about having a community under those sorts of capricious admins.

This sounds a lot like an automation of that process that misfired. That they were all specifically banned for being "unmoderated" is what jumps out to me as telling.