That's a pretty common criticism. But I find that most of these critiques break literature down to a single reductionist angle. In the same way there are multiple factors going into and out of Industrial Capitalism, and multiple affronts to ordinary human life, Literature is at its best a way of recapturing the subtleties of human life that are broken and corrupted by these systems.

There are some works which are less accessible to uneducated people, but whenever I watch The Daily Show or The Colbert Report with people who never went to college or don't often watch the news, they're often entirely confused as to the jokes and cultural references that are being made (many of them did not watch what on some nights seems like every movie from the eighties), the issues that are being covered (Citizens United is explained sometimes, but often the hosts simply assume their audience knows), and the political situation involved in a lot of it. Many of the same people will read the Bible on their own, and try to read Dickens, A Hundred Years of Solitude or Wuthering Heights without much difficulty provided they have enough time and there are footnotes. When I was working in forestry, I met several people who had only finished high school, but passed around a copy of Crime and Punishment quite eagerly when I had finished it. As time has gone by and I've spent more with actual working-class people, I find it's a pretty condescending thing to assume what's accessible to people who have less knowledge then you do, and often incredibly inaccurate. As it turns out, particularly those two shows are largely catered to the interests of college-educated news-watching, frankly, white people.

The other matter you're missing is that Marxism does itself require some level of moral, economic, and literary education (as in bare-bones understand how to read a long argument) to understand, and reading somewhat difficult literature has always been used to keep some of this in place. Marx himself advocated reading Dickens, Charlotte Brontë and Thackeray as important part of this education saying that they "have issued to the world more political and social truths than have been uttered by all the professional politicians, publicists and moralists put together."