https://www.techdirt.com/articles/20211012/17560147739/court-tells-arkansas-troopers-that-muting-anti-cop-terms-facebook-page-violates-1st-amendment.shtml

When government entities use private companies to interact with the public, it can cause some confusion. Fortunately, this isn't a new problem with no court precedent and/or legal guidelines. For years, government agencies have been utilizing Twitter, Facebook, Instagram, etc. to get their message out to the public and (a bit less frequently) listen to their comments and complaints.

Platforms can moderate content posted to accounts and pages run by public entities without troubling the First Amendment. Government account holders can do the same thing, but the rules aren't exactly the same. There are limits to what content moderation they can engage in on their own. A case involving former president Donald Trump's blocking of critics resulted in an Appeals Court decision that said this was censorship -- a form of viewpoint discrimination that violated these citizens' First Amendment rights.