Looking at the discussions further down it appears this list is a bit mistitled. It could more accurately be called "Authors who had a distinct style and a good body of work but weren't too influential". You'd have to drop Heinlein, but it would explain why everyone from Lovecraft to Gibson wasn't included.

I've got that one and a bunch of 19th and early-to-mid 20th century fantasy. In another comment I noted that Lin Carter's Ballantine Adult Fantasy series gives a superb overview of just how wide the literature of the Fantastic was pre-1960s and how much it narrowed afterwards. Tolkien became a genre and an industry.…

Tolkien has been so far surpassed that his influence is incidental? I'm having a hard time swallowing that.

So we can have some stars - Lem, Dick, Vonnegut - but not the Sun and Moon?

His was the tree that shaded out all the others. Look at the Ballantine Adult Fantasy series, probably the high water mark of fantastic literature. The one thing that stands out is the tremendous variety of the pre-LOTR biome. Afterwards there was an tremendous narrowing. Everything was the "next Tolkien". It was…

I'm working with what you provided.

Certainly in the eyes of people like the Van der Meers whose anthologies are the most critically accepted as representative of the genre. Absolutely for anyone who views Steampunk as a visual style.

Every writer owes "too much" to other writers.

He is one of the very few who could ever do linguistically-inspired fantasy on that level. The combination of world-class scholarship and superb storytelling ability is incredibly rare.

But they are considered the real definers of the genre.

How very interesting.

The gentleman echidna has four-pronged wedding tackle.

*deleted out of concern for delicate reader sensibilities*

Lovecraft, without a doubt the greatest omission and worthier than most of those on the list

Nice catch, that.

Horrible and unnatural - a plant and a fungus breeding.

Gordon Lightfoot could sing, and TWotEF was about something real.

And they wish only the morally disabled would comment on that song

Seq quis custodiet ipsos canachenes?

I find it painfully easy to look away from pictures of rotting food.