Never before in history has a small cabal of companies welded such power over what we can say and who we're able to associate with. In one concerted ban action, you can be cut off from most of your friends and the ability to express yourself in any forums that have more than a tiny reach. After being banned from the big three, you are now excluded from pretty much everything your friends do and say, and your chances in any political field are essentially zero. You even lose the ability to use many services that require the big three for authentication or verification.
Could you imagine the telephone company shutting off someone's phone service over something they said or who they associated with? Unthinkable. And yet here we are with the modern equivalent.
These companies have subsumed a not insignificant amount of power that was until now only within the purview of governments, with that power presumably subject to the will of the people and democratic ideals of free speech. You still weren't allowed to incite violence with your speech, for example, but investigation of that kind of behavior was the job of the police, and punishment the job of the justice system. And the bar was pretty high before censoring someone, as it should be in a non-totalitarian state.
These lawsuits need to happen because we NEED to delineate where responsibilities lay in terms of protecting our rights as free citizens. And that always starts with the most despised of society because they're almost always the ones to trigger these questions.
‘I disapprove of what you say, but I will defend to the death your right to say it’