Unconvertible assets

From Anthony Powell's The Valley of the Bones, here's the narrator Jenkins on literature's limited reach:

I was impressed to the ten thousandth time by the fact that literature illuminates life only for those to whom books are a necessity. Books are unconvertible assets, to be passed on only to those who possess them already.

This is the kind of thing that can sound like smug elitism, sombre resignation, or merely a sober view of the facts, depending on your mood.

It's actually all three.