SF hasn't had anything innovative and interesting since cyberpunk.
And fantasy hasn't had anything innovative and interesting since Tolkien.
And literary mainstream fiction hasn't had anything innovative and interesting since Faulkner.
Insofar as any of these are true, they are equally true. But the last is apparently even more relevant than I said. The SF/fantasy/horror literati writing reviews and giving interviews and awarding prizes and holding panels and blogging, blogging, blogging are equally pursuing literary mainstream ideals, which long ago drowned and rotted in a postmodernist morass. Trying to struggle for air in that muck certainly wore out poor Disch.
On the other hand, much as you pity his plight, it hardly seems very perceptive, or even very adult, to believe that book marketers have correctly seen through the pretenses of the readers and seen the truth: That Sf and fantasy and horror are all really just the same juvenile tripe. Thinking so may be hoped to be profitable but it's cheap cynicism.
There is a place for whimsy and froth, for metafictional games, camp and simple twee humor. But by and large most desires to merely ignore genre implies a desire to play games with the reader. Hiding the genre keeps the author's goal a secret. If the genre is a secret, then the restrictions (aka critical standards) for that genre can be blithely ignored. Unfortunately it fails to fulfil the implicit promise to fulfil genre expectation while simultaneously refusing either to recreate the genre or to subvert it. The only one who wins by this game is the author who gets to declare every shot hits the mark.
Eclecticism and obsession with superficialities of style historically have been hallmarks of decadent art.