Link back to commentAgreed. I think it's important to acknowledge that the tech giants are companies, not public utilities, and have the legal right to police their users' speech as they see fit. Personally, I think their left-leaning social agenda is much more profit motivated than ideological, though it's certainly true that the culture of the Bay Area is deeply leftist.
The shift towards policing described in your quote from Sinead McSweeney at Twitter is one reluctantly taken, even given ideological convictions. These companies have had to take on the massively complex task of policing their content in response to the anger of global mobs of political-correctness activists. They're simply doing what seems necessary to stay in the good graces of the public.
If history is a guide, Facebook and Google won't be hegemons for much longer. Technological change and nimbler competitors will send them the way of Microsoft and IBM. Facebook is already struggling with teenagers, who prefer to use newer, edgier platforms. Twitter, for all its social impact, has always been a company without a clear business model.
We also have to be clear what we're hoping for. Yes, it would be preferable if the social media platforms could take a stand for free speech. If they won't, government regulation is not the answer. The situation is simply too complex and too fast moving for there to be any hope of success for anti-free-market intervention. We laugh now at the meaningless exercise that was the Microsoft anti-trust finding in the 90s; I think we'll be doing the same in 15 years about any attempts to corral Google and Facebook.
Your points about China are deeply disturbing. It's unfortunate that Chinese economic power and our deeply ingrained cultural relativism prevent most politicians and public intellectuals from saying what is clearly true: The Chinese regime is a corrupt dictatorship whose rise is a tragedy for the Chinese people and an impending disaster for the world.