Not only is this an insult to adults who do not read the type of books Franzen deems as being morally complex enough, it is a direct slam against YA literature. What it reveals is a stunning lack of knowledge on Franzen's part. Anyone who has read widely can throw title after title that challenge Franzen's assertion about the moral simplicity of YA. I would argue further that YA, since its early roots, has provided readers with moral complexity. Consider two of the early YA novels: The Pigman by Paul Zindel and The Chocolate War by Robert Cormier. Franzen says that complexity means pointing toward the "possibility that you’re not the heroic figure you think of yourself as, that you might be the very dubious figure that other people think of you as." When I think of John and Lorraine and Jerry, I see this reflected in their own thoughts. Perhaps they are not "good." Perhaps they are flawed. Perhaps others are the same?
You want complexity, Franzen. YOU CAN'T HANDLE COMPLEXITY. At least you cannot if you have not read YA before you blast it (and what kind of moral simplicity is that, BTW?). I would suggest that Franzen sample the two books mentioned above and perhaps give I'll Give You the Sun and The Crossover to see the level of complexity that is in YA literature. Truth is good YA, like good adult books, is complex.
So, I will maintain my expectations, adjusting for the occasional Franzen.