An author, as the spigot through which art flows into the world, is allowed to attempt such a thing, but their editor is supposed to coax them back 'round to something readable--or at least to something that won't wake the typesetter in the middle of the night, screaming.
I mean, I know this conversation is all about railing against the snobbish "you just don't understand fine art" attitude, but I find the stubborn "he really needs to reign it in and not be so crazy" attitude to be unfortunate too. It's good for artists to experiment. A lot of those experiments can be very fun and enjoyable for the readers, if you're willing to give them a chance.
No, the artist is supposed to experiment. Someone on the business side is supposed to rein it in when the experiment turns to rubbish. Sometimes this quashes something great, but mostly it ensures that artistic professionals can be supported by their own work.
But it is particularly unfortunate when such an experiment escapes into the wild, and a clique seizes upon it as a test for tribal identification.
It's okay to dislike "great literature" and enjoy "pablum for the lowest common denominator" or "escapism for immature minds". I don't really find a whole lot of value in critiquing other people's preferences. If you don't like a specific artwork, you should just keep sampling until you find something you do enjoy, no matter who else likes it. You're not going to make yourself happy by forcing yourself to like something just to fit in to a social group; you're far better off being honest with yourself. After all, you never really know if it's an Emperor's New Clothes situation until someone speaks up and says "I hated every word of this book, and I have no idea why anyone would think it's a masterpiece."
It may well be that will be followed up by "I only said I liked it so that you guys would think I was intelligent and cultured", "I read it in bed because it was such a reliable way to make me fall asleep", "I only read like a third of Gravity's Rainbow, and faked the rest of the way through for book club".