AND, if you have read the book, you will honestly admit that every word of the rejection is true.
Ursula K. Le Guin writes extremely well. [snip] The book is so endlessly complicated by details of reference and information [...] that the very action of the story seems to be to become hopelessly bogged down [snip]
Yep. That's UKL, and that's LHOD. And many readers, including myself*, loved it that way.
The rejection is implicitly indicating that the Editor is looking for more action-oriented speculative fiction, whereas UKL's work is more contemplative and theme-oriented. There's nothing intrinsically wrong with the editor or the book, they just aren't a match.
Don't engage in rejectomancy. "No" means "no", and that is all.
*Darn, I can't figure whether that should be "including [me, myself or I]", and I don't care enough to look it up. I think that me or myself are both acceptable. Tricia?