As an american you don't have the right while in mainland china to criticize the CCP. While there is no simple way to apply sovereignty to the internet, the decision to follow the laws of the participants countries seems relatively reasonable.
If you are a Chinese citizen you can be arrested for sharing content the Party objects to, even if you were overseas when you did it[1]. You do not even have to be inside China or a Chinese citizen, the authorities may still kidnap and imprison you for exercising your right to free speech in jurisdictions where it is not restricted[2]. So it seems like it doesn't really matter to the Chinese government what the laws are in other countries, when it comes to suppressing speech.
Meanwhile, Chinese officials and propaganda outlets continue to enjoy full freedom of speech in both social media and traditional media in the west.
[1] https://www.axios.com/china-arrests-university-minnesota-twi...
[2] https://en.wikipedia.org/wiki/Causeway_Bay_Books_disappearan...
On your examples: CCP sees some speech as national security issues, which in itself is not controversial i.e. wikileaks. On Luo Daiqing in, countries have subject matter jurisdiction, laws that apply to citizens at all times and regardless of location, i.e. treason. If certain speech is outlawed in China then Chinese nationals can legally be prosecuted by China for them regardless of jurisdiction. Other countries have same legal arrangements on other issue, i.e. sex tourism, organ transplants, drug use. Causeway Books is more complicated, HK(Chinese) and foreign nationals operating in HK to distributed banned books to customers IN mainland which is illegal but also un-prosecutable due to lack of extradition treaty with HK. Basically the reason behind current HK national security law designed to close one-country security loopholes. CCP believes selling illegal books to mainland undermines national security. It was less of a free speech issue than shenanigans comparable to foreign NGO meddling that CCP thinks jeopardizes one-country national security and worth expending political capita on to control. Since national security in context of one-country was legally undefined, CCP was forced to resort to coerce or rendition. It's like how the west will prosecute whistleblowers wherever they are, sometimes through extraordinary means, no matter the optics. Even though in this context the book sellers were (from my understanding) peddling salacious gossip.
It seems if Assange leaked Chinese government info, as a non-Chinese citizen, he wouldnt be in jail right now.
A great feature of Americans looking at China, is they gain an awareness of how the rest of the world views the US in its many areas of overreach.
I think it's an important distinction. Might doesn't make right.