Arguing that the free market can provide an alternative to Facebook, while possible, is extremely EXTREMELY difficult. And I say that as a free market advocate myself.
If the original AT&T prior to the breakup had the power to monitor telephone conversations and choose who got to use its service based on political opinion of the customers, they wouldn't have gotten away with it. If they COULD, well... does anyone really think that establishing a competing utility would be a viable option?
Facebook has become a monopoly and worse. It is effectively a cyber superpower nation state with a power-mad geek as its authoritarian tyrant who in some form or another is affecting the lives of EVERYONE.
Time to bust Facebook up.
Where does the Constitution authorize the feds to do that?