I think you are making a mistake in assuming that the social dynamics around censorship in China are fundamentally that different from the ones around censorship in the US or other countries.
You could similarly argue that it is "funny" how every US business that builds something that can move around information must be knowledgeable about statistics that break down criminality or IQ by census race, or biological sex differences, or all manners of other "forbidden" information - but of course as members of the same social stratum as the people involved in such businesses in the US, we are not actually that worried about the possibility that our fellow tech elites will see the information they were supposed to censor and come in droves to want to introduce slavery or the Handmaid's Tale world or whatever. We consider the "forbidden" information merely wrong, evil, misguided or miscontextualised, and broadly trust our peers to see it in the same way. The real danger is instead if some other people, parts of the scary masses we don't have a good grasp of, are exposed to those memes and are misled into drawing conclusions that we know to be inappropriate, or at least unacceptable.
It's easy to imagine that a Chinese LLM wrangler would feel much the same: trustworthy, well-adjusted people know about Tiananmen Square and the Uyghurs anyway but understand that this information has to be seen in context and is prone to be interpreted in problematic ways, but who knows what would happen if we allowed uneducated and naive people to be exposed to it, and be led astray by cynical demagogues and foreign agitators?