1. As a US citizen, you would probably not a get permit necessary for entering the Tibet region.
2. If you could get a permit for Tibet region and go there, you would be followed by police officers dressed in civilian clothing. The locals would be quite hesitant to speak to you.
(Source: been there long ago, seen it). China has many qualities, but freedom is not one of them.
I don't think the poster you're responding to is writing in good faith; they're either an agent of an authoritarian power, or blind to the difference of being one.
People in China can say anything the government approves of, but they can't say "long live freedom and democracy," unless they want to be executed.
Neither, I suspect, will Chinese AI models make any statement in sympathy with personal freedom, democracy, or human rights; it would come at the expense of the people who paid to train those models, and that can't be allowed.