This is purely a hypothesis, but our generation has been raised to believe that failure is a bad thing, that must be avoided at all costs, rather than something that happens and is learned from.
Having a successful career meant going to a top college, which meant getting straight As in AP classes in High School. This mentality continues through college. Want to be a lawyer? The only way you are going to do that with any success these days is to go to one of about a dozen law schools, which getting anything less than a 3.5 GPA pretty well disqualifies you from. Want to be a doctor? It takes a similar GPA to get into med school.
I'm going to have to disagree to some extent in that "our generation" is not more risk-averse than past generations. Past generations had you graduate from college and success was often defined by working at one company for your entire life, possibly rising in the ranks slowly. Becoming a lawyer and becoming a doctor have a pretty set path -- if you're going to be doing open-heart surgeries I don't want you to keep "failing fast" (startup speak, I know). If anything, in this post-The Social Network world, even if some people's motives aren't there, I still think people are embracing entrepreneurship more than in many other previous generations.
Having a successful career meant going to a top college, which meant getting straight As in AP classes in High School. This mentality continues through college. Want to be a lawyer? The only way you are going to do that with any success these days is to go to one of about a dozen law schools, which getting anything less than a 3.5 GPA pretty well disqualifies you from. Want to be a doctor? It takes a similar GPA to get into med school.