Literature, as a form of art, really is about the culture from which it originates from and that culture which is the subject. Any personal "enrichment" by a reader, regardless of the material, is based on their subjective experience. Whether the take-away experience positively or negatively affects the reader... I can't see how any valid generalization can be made beyond, "it may or may not happen, and to the degree and quality, that is indeterminate." The only thing we can really verifiably say is that the reader participated in the cultural narrative.