Do you really think that they are simply censoring general political opinion? That would render their websites complete echo chambers or seriously boring. What they are censoring is the kind of content that attracts the mentally ill to behave in ways that causes harm to others or videos of people being physically harmed for amusement. These are the kind of things that they would be sued for aiding and abetting either out of negligence or because of a profit motive if people were harmed because they did nothing. Believe me, they are not that political - they are first and foremost capitalists. Killing the very thing that attracts people to their websites is not in their best interests, but they have been accused of tolerating, if not providing a platform for social deviants who extol and revel in violence.