It may be that a partial explanation for this …

Furthermore, “It was not manly to put a lot of time and effort into academics,” said Edwards. It’s not cool to study, to read the book: “Sometimes it’s not cool to even buy the book. But you’ve got to ace the test. You’ve got to make the grade,” continued Edwards, who described male students studying on the sly, telling their buddies they were spending the evening with their girlfriends and then hitting the books instead. “The script to be a manly man means you’re good at everything and you don’t have to work at it,” he explained.

… may be found in my observation that our society seems increasingly to insist that all heroes be superheroes, often on top of being counter-cultural antiheroes. It’s not that there are no role models so much as that those who are available are inadequate to the promoted ideals, and that the promoted ideals are increasingly narrow in variety.
We see the chiseled actors and shapely actresses, but we too seldom recall that being fit and attractive is a large component of their job. We see the natural ease with which characters have mastered impossible bodies of knowledge and limitless mechanical knacks, but we miss the indications that it is all an illusion created by teams of researchers and writers.
In the case of college men, I’d suggest that these factors intermix with the long-running vilification of males in such a way as to make an ordinary fellow feel suspect. They must either transcend the rules or be mired in the original sin of their own masculinity within them. That the researchers in the first link above suggest that all students be subjected to a course in women’s studies shows how terribly little they understand about their subjects.
One initial stage of a remedy for a multitude of societal problems would be to stop pushing all young adults into college as if it must be an extension of high school. Let the kids work for a few years, routing about in our civilization for a broader sense of the possibilities, both for career and for identity. Those who then return to higher education will be more confident and better oriented toward their purpose.
Of course, they’ll also be less easily manipulable, which may be an objection in some quarters.
(via Instapundit)