Ovinomancer
No flips for you!
The quote is still about not using “extra” words. It still implies that brevity is better, unless more words are necessary to tell the story.
The irony here is that you completely misunderstand Le Guin's words and yet are telling others what good writing is. Le Guin's advice is more of a truism -- it's good when it's good, and the addition or subtraction of more words defeats that. As such, it really can't be argued again, because it's merely saying that it's right when it's right and offers no real advice on when that is. But, here, you're insisting that it "implies" brevity, which is surely does not. It's like cooking and adding salt; too much or too little will make an otherwise perfect dish into a lesser version of itself.
On topic, Tolkien is a poor novelist. He doesn't follow the normal structure, and his changes do not enhance his story, so it's not a matter of stepping outside the box and still hitting it out of the novel writing park (to mix metaphors). He is, though, a good writer. And, for the LotR, his goal really wasn't to write a novel, but to present his world. So, he bends his talents to building and exploring that world, which makes for a poor novel. You can love it for his worldcraft -- it's tremendous -- and even the scope of his tale, but the actual execution is poorly done. It's like reading a picture book, but on every page you have to wait while the illustrator draws a masterpiece. If you're reading the story for the story, this is tedious. If you're wanting to enjoy the glorious illustrations and soak in their craftsmanship, then you'll love it. So, bad books, amazing worldbuilding. It's all a matter of what you're seeking in them.
And it has nothing to do with post-moderism, which has been used as a buzzword when it has little to do with the discussion so far.