The temptation is strong, when encountering views one dislikes, to regard the person expressing them as disingenuous and pushing some sinister agenda. This is why the site guidelines explicitly say "Please don't impute astroturfing or shillage. That degrades discussion and is usually mistaken. If you're worried, email us and we'll look at the data."
As geopolitics between China and the West heat up for reasons totally beyond this site, users here need to remember that HN is an international community where all are welcome. Being welcome, among other things, means not being slurred because of your national origin, language, race, and so on. It's nice that HN feels like a small and intimate place, but it's not a living room—when you post here, you're broadcasting to an audience of millions. Many come from very different backgrounds than you or I or any of us does, and they have just as much a right to be here as you and I and any of us does.
The image of "warding off Chinese commenters", which you invoked in your comment upthread, is dismaying and exactly what we don't want here. People need to listen to each other more, not less, when there is distance between them. I don't want to be part of any site that works against that.
I’ve related a dismaying image because the reality is dismaying. One group of (mostly awful and hateful) Internet users “wards off” another by copy-pasting what are to them, for all intents and purposes, magical runes. Scribe them down and the others disappear, banished by some arcane and unseen force. The crazy thing is that these runes may actually work, because the targeted users live under a system of censorship and surveillance unprecedented in its scope, scale, and level of detail.
That’s nuts. It’s utterly fascinating. It’s (the block-text posting) not behavior to be emulated anywhere on HN. It is absolutely dismaying. And as a story, it’s also completely on-topic and within site guidelines.
Are all positive comments about China made by the “wumao army?” Of course not. Are many such comments astroturfed (Edit for clarification: speaking of the broader Internet)? Absolutely. Would it be racist to point out the existence of the large and well-funded groups paid to make such comments? I don’t think so.
Obviously, this isn’t a cudgel to be used against any pro-Chinese government comment or argument. “Wumao” is often employed as a slur. But it is 100% a real phenomenon.
http://news.bbc.co.uk/2/hi/asia-pacific/7783640.stm
https://en.wikipedia.org/wiki/50_Cent_Party
https://en.wikipedia.org/wiki/Internet_Water_Army
https://youtu.be/yCnnPf2OnHo