This is almost exactly what some people started saying almost 50 years ago[!] when the New Wave writers started rewriting science fiction. Where’s the gosh-wow? Where’s the glory and scope and heroism?
It’s popped up probably annually from somebody somewhere in the intervening years. Of the three major professional science fiction magazines, Asimov’s and F&SF are almost entirely literary and Analog is almost entirely not. The audiences have about the same regard for one another as rock and country music audiences. I.e., there is a tiny bit of overlap and heaps of contempt tending toward hate.
When Philip Pullman and others entered young adult writing, the same backlash appeared. Darkness doesn’t belong in children’s books, said some, ignoring all of history.
Horror went through a phase of violent bloodiness called splatterpunk and the hatred was palpable. Longer ago than any of these, the whodunit fans and hardboiled fans said exactly the same thing.
Romance has been torn apart over and over as more sexual liberation is allowed into the field. The virgin book audience hates the slut book audience and the latter hates the priggishness of the former.
So I’m hardly surprised that somebody is saying it about fantasy. And remember the source. The BigHollywood blog is devoted to castigating liberalism in all media, in the most extravagant terms. The literary/gosh wow split in sf sundered fans and writers in exactly the same liberal/conservative way, and spilled over into virtual warfare over U.S. Viet Nam policy. (In 1975 I sat next to a Very Famous Writer at the Nebula banquet, only to have him say to me that all wars were the fault of the Democratic party. Must have been the length of my hair…)
None of it matters in the tiniest. It’s a big field. They’re all big fields. If you don’t like certain types of writing, there is more of your style being published than you can possibly read. People being people, they will always look down upon what others like, no matter what that is. Read the blog, get outraged or nod in agreement, whatever your preferences are. Then forget it. And go read what you like.