I agree that Facebook's censorship of content, as well as their on-going attempts to debunk whatever they happen to define as "fake news" is extremely problematic and scary. However, this isn't really a First Amendment issue. The Bill of Rights is a set of legal guarantees for citizens against their government. Now, the government can pass laws limiting Facebook's ability to censor people in the same way that there are laws prohibiting things like banning African Americans from eating at certain restaurants, etc. I don't know if that's the right answer, though. I don't see Steemit as a decentralized replacement for Facebook, but do you know much about Akash? (akash.world)