"Arbiter of truth" is too big of a word.
People easily forget two important things:
Facebook is a social media, emphasis on media: it allows the dissemination of content, it does not produce it;
Facebook is a private, for profit enterprise: it exists to generate a revenue, not to provide a service to citizens.
Force 1 obviously acts against any censoring or control besides what is strictly illegal, but force 2 pushes for the creation of an environment that is customer friendly. That is the only reason why there is some form of control on the content published: because doing otherwise would lose customers.
People are silly if they delegate the responsibility of verifying the truth of a content to the transport layer, and the only reason that a flag button is present is because doing otherwise would lose customers.
That said, to answer your question:
No, Facebook does not have any responsability beyond what is strictly illegal. That from power comes responsibility is a silly implication written in a comic book, but it's not true in real life (it's almost the opposite). As a general rule of life, do not acquire your facts from comics.
"That from power comes responsibility is a silly implication written in a comic book, but it's not true in real life (it's almost the opposite). "
Evidence? I 100% disagree with your claim. Looking at governments or business, the people with more power tend to have a lot of responsibility both to other people in the gov't/company and to the gov't/company itself. The only kind of power I can think of that doesn't come with some responsibility is gun ownership. Even Facebook's power of content distribution comes with a responsibility to monetize, which then has downstream responsibilities.
If it's worth saying, but not worth its own post, then it goes here.
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