Your link is inane pedantry. Capitalism is the word we use to refer to a free market society. The origin of the word is irrelevant.
1) Nope. Companies to not get to decide the law. Nations get to do it. Yes, a moronic nation may leave it up to the contract, but in that case slavery would be legal. He who has the power of police makes the rules.
2) I do not use social media (unless you consider slashdot to be one). But others do, and people believe it has negative influences, mainly by spreading lies, propaganda, cults, etc. Government has the right to regulate it.
3) There is no 'basic human right of freedom of contract". You have elevated something you want to something much larger. We are not talking about marriage or friendship, those do have basic human rights, but they are NOT mere contracts and are protected by other rights. We are talking about Facebook, not marriage and if you do not see the difference, I pity you.. Trying to pretend that this is a larger principle is how scumbags convince people of lies.
Basically you are believe the equivalent of 'I have the 2nd amendment right to walk around with a bucket of acid you cannot blame me if occasionally some spills."
NOPE.