Which is BAD. Trying to conform to the tropes of a genre is limiting and makes for dull repetitive fiction.
And many critics are genre snobs. They rate fiction much more harshly if it contains science fiction or fantasy elements...
...and rate it higher if it wallows in misery.
That is quite a limited take on Orwell, Atwood, and Burroughs. If that is your takeaway on those three highly distinct, disparate authors, then it's hard to take your opinion of them seriously (wallows in misery? Atwood? Really?).
I think there is some genre snobbery, sure. But it is also true that there is a lot of best selling genre fiction that is, by literary standards, very, very basic. Let's set sci-fi aside so as not to ruffle any feathers: the Twilight series has sold tens of millions of copies, and the Shades of Grey series, which is basically Twilight smut, tens of millions more. I have trouble not laughing out loud when I read some of the terrible sentences that those authors have published...but they have made a fortune, so what do I know? So the snobbery is not without basis: there is a vast market for genre fiction that is, by literary standards, barely readable. As far as writing ability goes, most of the authors mentioned in this thread are basic.
And that's fine. I love punk rock, and it's not because of the musicianship. Art is subjective and contextual, so if the tools get you where you need to go, then bless. But the idea that genre is just a marketing tool is wrong. Genre
greatly impacts writing, and there are a lot of genre writers who are successful because they are writing in that niche.
Take
The Martian. That is a book that I greatly enjoy; I've not only read it several times, I've taught it as part of a creative writing unit on episodic storytelling. But Andy Weir is an extremely limited writer. His characters are unoriginal and lack distinctiveness, and his prose is very mundane.
The Martian works because he stays in his lane: he uses science to generate compelling plot points and to keep the reader engaged by Mark Watney's ingenuity, by his capacity to use science to solve seemingly intractable problems. Andy Weir is never going to write the Next Great American Novel; he's not good enough. But I don't care; if he can give me more books on par with
The Martian I will be more than satisfied (that said, his next two books: readable, but not nearly as good). Genre is not really a "ghetto", it provides alternative contexts through which to understand and value art. Genre is a good thing. I am proud to be a sci-fi fan.