There's no censorship here. A large account broke their contract with a service provider, who is now choosing to suspend (not terminate) their account in response. Seems like a perfectly free and legal exchange to me.
The point here is the risk of our social communications being concentrated via a few large companies, who have ended up with an enormous amount of power to control speech online globally.
Unless you want to make the claim that speakers are entitled to audiences, that is.
I'm not arguing you're entitle to an audience, either, just that taking your speech from a major player to a much smaller niche player is not nearly equivalent.
Maybe I'm just dense, but I'm not seeing the cost differential, either for the speaker or audience. What Facebook is doing is equivalent to saying "you don't have to go home, but you can't stay here." What's so wrong about that?
Just because something is legal doesn’t mean it’s not censorship.