While of course the speech freedom is pretty scarce in China, there are many things that the USG do without the legal ability.
Also, the massive attempt to deplatform Trump supporters also significant weakened my belief in the US's speech freedom. I don't care if this was done by the USG or private companies, but it worked, very effectively, Parler was gone in the same way as Twitter get GFWed in China. I was shocked how Chinese this was. As a Chinese and for personal experiences, I hate Trump and the red-necks to the deepest, but I would support their right for emitting their sound.
Trump used twitter to incite violence and insurrection, which is not protected by the first amendment.
It would be better to determine this through the courts rather than twitter, but twitter has every right to ban trolls, spammers, and politicians calling for violent action
The same would be also applicable, if stretched a little bit, to protests and people organizing them in China. "Weibo has every right to ban trolls, spammers, and politicians calling for violent action" (Weibo is the Chinese Twitter equivalent)
We should not have double standard just because the USG is a something you like and CPC is not.
