If you don't like Facebook's censorship policies, don't use Facebook.

I suppose an argument could be made that due to its size, Facebook is sort of like a "utility" and has a duty to provide "service" to everybody regardless of its opinions about their use of the service. But unlike the electric company, which is the only place you can buy electricity, Facebook is not a monopoly: There are plenty of other websites where you can publish your speech (or you can even get your own domain and VPS and host your own site very cheaply).