You've misread/misunderstood the book review. It's saying the exact opposite, and the same thing as you; that in the book, the aliens are more like westerners, and the humans Chinese.
The thesis as given - "The real aliens are the Chinese people" (note the 'real') - is saying that, to an American reading the book, the portrayal of the humans feels more alien than the extraterrestrial aliens, while the extraterrestrial aliens are closer to familiar western culture.
The thesis as given - "The real aliens are the Chinese people" (note the 'real') - is saying that, to an American reading the book, the portrayal of the humans feels more alien than the extraterrestrial aliens, while the extraterrestrial aliens are closer to familiar western culture.