It's a bit like Jean Michel Jarre's concerts in China. It's not by far the best that we've produced but it was the first to be performed at that scale in a culture that had relatively little contact with Western music. The flip side is that very few Chinese books make it to the West in translation, and as such it is both a first and a sample at the same time, it may not be the greatest book ever written but it certainly isn't the worst either. Hailing it as a masterpiece is a bit over the top but then again, if that incentivizes publishers to translate more books from Chinese to English then it has my vote.

FWIW I'm pretty old school when it comes to SF and found it readable but certainly not at the level of the holy trinity.