Hopefully I don't get dang'd by observing how common a meme this is.
Companies, public and private, have the legal right to take on whatever political position they have, and beyond having the power to control dialogue, there is no way they can abdicate exercising that power; it's unavoidably emergent from their technology that someone's tweet has to show up top when you log in. This extends to anyone that writes code connecting a query to some media content.
Since asking for Government intervention in this realm is highly illiberal, the exercise of this power is a matter of corporate social responsibility. And how the CSR shakes out around the use of a platform to encourage hate and violence of any stripe is a point of contention.