Might have missed something here, but surely the preferred method of expressing discontent to a content consuming service as a content creator is to deny access to your content.
Doing so publicly and alongside other small content producers — maybe even creating an alternative space to host said content -would presumably create the sort of fuss that would make FB sit up and take notice.
No requirement for expensive legal battles. Winning public opinion, etc.
Like I said, maybe I missed part of the discussion.