The argument may not be as old as "literature", but it certainly must be as old as narrative: which is the part of the story that gives it real value? Is it the suspense in the narrative? Is it the style, the interesting ways in which the words interrelate? Is it how vivid the characters are? Is it how entertainingly you describe acts of sex or violence?
Over at Salon, Laura Miller (author of the fun The Magician's Book: A Skeptic's Adventures in Narnia), revisits this ancient non-controversy (let me ruin the suspense: it's the punctuation). Edward Docx (whose name was probably perfectly reasonable before the advent of Word 2007) apparently wrote a denunciation of those who read Stieg Larsson and Dan Brown, one I am not going to read before rendering judgment on it.
Most such screeds go after the easy target: genre. It's not turgidly written literary novels or academic post-modern exercises that get the laser pointer on their foreheads. It's suspense novels, mystery novels, science fiction novels.
Why? Because a genre is an agreed-upon set of conventions that let you take certain aspects of the novelistic work as given, so that you can focus on those that of more interest to your readers. And your readers are the ones who determine what you do and how you do it. If you come from outside a genre you might get irritated at these conventions, and interpret them as restrictive rather than liberating. Interpreting the genre as restrictive leads you to interpret that authors as restrictors, and the readers as codependent victims in a sadistic game.
And, of course, genre restrictions can be tiresome. Do we really need another whore with a heart of gold, or cynic hiding the heart of a self-sacrificing idealist? Genre doesn't generally like ambiguous characters with situation-dependent personal traits. Those lead to the kind of work that genre has specifically excluded.
Genre is a labor-saving device, and only the wackiest grad student would think that "labor" is what most readers are looking for.
Sometimes, of course, they are. And given the right cookies, some readers can be interested in slippery narrative techniques or sentences with endless dependent clauses. But there are plenty who can't.
Truth in advertising: I am allergic to clunky prose and often can't read perfectly fine and popular books in my own genre (science fiction) because I find their sentences and their characters uninteresting. I think a bit of spark in your prose is perfectly OK. Sometimes I feel guilty about this covert mandarin attitude, but usually I don't.
But to a genre reader, the prose is the window through which the events of the book are seen. If the prose calls attention to itself, it's like dead bugs on the glass. What is "transparent" varies from reader to reader, of course, and seemingly clear prose from previous eras is anything but. I presume Dickens read like...well, not like Dan Brown, who really is appalling...but like Michael Crichton or Suzanne Collins to his audience. Now you notice his emotion-manipulating characters and long sentences. You would not have at the time he was churning them out.
So its legitimate to call for, and hold yourself to, higher standards. But you have to know what all the parts do before you start monkeying with them. Complaining that the blades of a fan are too plain and clunky, and would look much better with the four winds engraved on them, misses the fact that a fan's purpose is to blow air, and you can't see any artwork on the blades when it's in operation.
I love a good sentence. But if I love a good sentence, is writing science fiction really the best way to create one? The jury's still out on that one, I think. But I will continue to try to create them.