"Earlier this year, I noticed something in China that really surprised me. I realized I felt more comfortable discussing controversial ideas in Beijing than in San Francisco. I didn’t feel completely comfortable—this was China, after all—just more comfortable than at home."
That particular quote seems to come up every once in a while, and I still don't quite get why people feel it's profound or important. China has a very public and well-known list of things that you are not allowed to talk about (Tienanmen Square, a few others). SF doesn't (or didn't) because what was offensive or violated whatever new rule the way-too-online wasn't codified as part of some legal apparatus, it was/is very dynamic. One does not need to actually go to China to recognize this.
"Earlier this year, I noticed something in China that really surprised me. I realized I felt more comfortable discussing controversial ideas in Beijing than in San Francisco. I didn’t feel completely comfortable—this was China, after all—just more comfortable than at home."
https://blog.samaltman.com/e-pur-si-muove
He also mentions giving a talk for YC in China in 2018:
https://blog.samaltman.com/idea-generation