This can be as devastating class action law suit. If enough people start exercising their right to arbitration it can get VERY costly for Facebook.

I can’t find the story now, but there was a case in I think California of a company suing to get out of an arbitration clause, wanting instead to move to a class action lawsuit. Thousands of arbitrations became time consuming and costly. So I think there is still big potential for a coordinated effort to make this difficult for Facebook, even if a class action suite were off the table.