Happened to page through the first three pages of Joyland, the paperback copy lying on the floor next to the couch where I read. There's three pages of blurbs from an assortment of newspapers, magazines...all gushing about Stephen King...one from the NYT-BR...a piece of that blurb, "his real genius is for the everyday." I think he was accepted at the beginning, no? I don't recall reading of rejection after rejection as I have for many other writers. I read a story from Elmore Leonard recently, a story that was written after he'd been established, and he had to wait ten years before it was published. Seems like that'd be a kind of rejection, the ten-year wait.
I think what you are asking is he accepted by the whatever, the A-Team of critics, whom-so-ever they are. One name comes to the tip of my mind and stays there in the shadows...James Someone...Woods maybe. I'd be surprised if he reviewed King. I wonder how much King is read in high school or college? That might be a clue. Read one review of Lisey's Story...in Salon I think it was...the critic, a female as I recall though not her name...took him to task for the magic in the story, the magical realism, Booya Moon and the Long Boy. Said he couldn't leave that out of his story though he tried. Empty devils. Heh! King's use the Shakespeare's The Tempest in that story, I suspect, says what I believe King thinks about that angle. If you haven't read The Tempest, you should.