On your first issue I can't really talk on this as I don't know what specific criticisms you're talking about and people who are on here and in general are not a hive mind and believe different things for different reasons. However if I were to make an educated guess I would say most of it comes down to stick in your eye Vs speck in ours as you fall sort of generally under the status of US client state and at current most of Europe, the US and their client states are sliding fast and hard towards fascism once again.

On your first experience that sounds like an extreme reaction by any chance do you remember what you said specifically? On the firewall more generally: The firewall was created to foster and protect China’s fledgling digital infrastructure and data sovereignty. China built its own ecosystem instead of depending on foreign companies. We have seen what happens when foreign platforms operate with impunity: Facebook facilitating genocide in Myanmar, coordinated anti-vax disinformation campaigns in Southeast Asia, algorithm-driven radicalization. The firewall makes those kinds of external influence operations far harder or close to impossible to run at scale. I support it and so do many others as the alternative is plain to see.

On the second experience again I'd have to hear the joke it is possible you said something racist bigoted or otherwise harmful without realising due to possibly lacking context. Also it's CPC not CCP. CCP is the acronym pushed by the US to attempt to pull it closer to the CCCP in people's mind so they can reuse coldwar/redscare propaganda.

Then on your third experience again hard to say without knowing exactly what their criticism was but sounds like they had their own issues.

On your closing paragraph I think 3 anecdotes really doesn't give a good view of a society of 1.4 billion people, in reality criticism is extremely common from didi drivers to friends to colleagues and smalltalk. Not to mind the local party offices whose entire purpose is recieving feedback and criticisms and then acting on them to build up merit to be able to run for higher office.

On communist Lemmy communities I really rarely see people being called US bots, in fact I have never once seen it. If you come in regurgitating propaganda with a smug attitude and doubling down in the face of facts contrary to your narrative you'll definitely get some sharp responses, however people seem to generally prefer to educate than deride so long as you ask in good faith and are polite (communists also appear to want to minimise ableist or dehumanising language even against people they don't like as opposed to the more "liberal" instances). On the other hand what is extremely common and has happened to me personally many times is non communist Lemmy instance users calling me and others a bot, brainwashed, shill, government agent etc. when its pointed out that reality doesn't actually match with the narratives they have internalised.

I think if you have genuine curiosity and questions you should try asking around on communities like AskLemmygrad or any other other lemmy.ml, hexbear, lemmygrad communist communities that take questions and you'll likely be pleasantly surprised.

Do note that these three anecdotes, particularly without complete context, do not paint an accurate nor complete picture on their own.

That being said, you're replying to a very knowledgeable Chinese user who I'm sure can help clear things up if you're open for it.

Not just China, no country on earth should be naive enough to let the US surveillance corporations operate within their borders. Here's a good video on why the PRC keeps them out.

But all these experiences tell me Chinese society is not accepting of even apparent criticism, which does not look like a free society to me.

The PRC doesn't just allow criticism and freedom of speech, it acts on it, unlike western countries where everyone (arguably) has the freedom to shout into the void and change nothing. The CPC is the world's biggest pollster, which constantly gets feedback from its citizens, and acts on them.