On top of blocking thousands of websites (which includes Facebook, Google, Twitter) China's government employs thousands of government employees just to purge even the most mild criticism of the CCP on Weibo [1]. They also employ tens of thousands to export their propaganda overseas, using sock puppet accounts to push their worldview[2]. And their worldview is fiercely anti-democratic.
The Internet cannot remain free if we allow governments to use their power to control narratives and suppress the truth. US-based Social media companies are not ideal judges, but at least they publish their methodology and allow public criticism of their platforms.
[1] https://en.wikipedia.org/wiki/Sina_Weibo#Censorship [2] https://en.wikipedia.org/wiki/50_Cent_Party