True. Facebook is NOT the government. There’s a big difference between one entity denying us the use of their services, but it is a different ballgame altogether when any level of government acts to arbitrarily deny someone their First Amendment right to free speech.
Another argument in our favor: When it comes to “listening” and “being heard in the cyberspace town square”, there is NO suitable alternative for the Internet. It is well-established law that the government cannot suppress all free speech as a means of suppressing illegal speech.