I see absolutely no reason why you couldn’t be a Dev and an admin, in a decentralized platform. If this was a single-server platform, maybe. But here, how does the moderation policy of lemmy.ml affects anything but posts over there?
Also, beehaw has a very politicized banning policy, would you say that is unacceptable? I see it as perfectly fine and I would be fine as well if they were to contribute to Lemmy code (unless they try to build their policies into the code and therefore enforce them everywhere - which is something we know the Lemmy devs are not doing).