I have been reading the English translations and the characters and especially their dialogues feel very fake. I do appreciate the hard science aspect of the books but the long monologues, kids speaking like middle-aged philosophers, and army personnel being one-dimensional macho men breaks the immersion for me. It has the depth of a 1980s low-budget thriller.
I don’t read a lot of hard science fiction or translations of Chinese books. I don’t know if this is genre-related.
I loved this series but I consider the characters as a vehicle for the ideas. It’s not really a character-driven work; the author is more interested in how humanity as a whole would react to his fictional scenario than he is with writing characters with depth. I wouldn’t necessarily say it’s related to the genre but there are a lot of examples of this type of writing in science fiction. I also loved Dune but I feel the same way about its characters to some extent.
This was my impression as well and I think it works only because the fictional scenarios are extremely creative along with sometimes gratuitous science-fiction details from the author’s imagination. And even though most characters seemed unrealistic as people I still liked them as characters and found them memorable.
I also read (listened to) Voyagers by Ben Bova recently and while the fictional scenario was interesting, the character development leaned heavily on the relationship between the hero scientist and the promiscuous young scientist, a writing style which I found more boring.