I think he's saying the ideas are good, but characterization sucks. I might compare it to Asimov: one would never read Asimov for the characters or the psychological insight (like one would read Tolstoy), but one reads Asimov for the plot and the ideas. It's not for everyone, but you would need to read the book to see if it's for you. To say just read the Wikipedia articles would be unjust.

My advice: read it if you liked Asimov or learning about Chinese culture. For example, another commenter pointed out one theme in this trilogy is "The most powerful human trait is the ability to hide ones true feelings and thoughts from others". This is a markedly Chinese trait that it was noted by a missionary who visited China in the 19th century and wrote a book called "Chinese Characteristics".