China isn't North Korea. There's a lot of travel of both Westerners and Chinese into and out of China, and free-ish communication between them. Within China, you can talk about many things privately without having to worry about the police showing up. The government's big red lines are public advocacy and especially political organization.
Fear No Evil by Natan Sharansky describes a similar situation in the Soviet Union: https://www.amazon.com/Fear-No-Evil-Natan-Sharansky/dp/18916.... (As in aside, is there a Chinese translation?)
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