Funny that you chose Dickens, who deliberately made his books longer than necessary, inventing subplots that had little or nothing to do with the main narrative (see Bleak House), because his novels were serialized and he got paid by the word.
Literary fiction and marketable fiction are not mutually exclusive terms. For recent examples, look at Franzen, Margaret Atwood, or Donna Tartt, to name a few random ones: all sell well commercially and call for scholarly examination.
Whether it’s what we call literary or genre, fiction needs to be worth the reader’s time, even more so now in light of all the more accessible mediums it has to compete against for that time. If the current state of the competition means less navel-gazing novels on the shelves, full of grad-school prose and characters who sit looking out of windows ruminating, I see that as a positive.