Going to an elite school
1. denies you the opportunity to empathize with anyone beyond a narrow spectrum of socioeconomics and culture
2. anoints you with a sense of self-worth and entitlement that is, if earned at all, only founded on a narrow set of skills: analytic ability and hard work
3. admits you into the class of seductive "entitled mediocrity", which allows you to fail spectacularly with essentially no real repercussions
4. constraints you, via social pressure, to a narrow set of "prestigious" career paths, among which you might not find the one that is truly right for you
5. shelters you from failure and encourages the idea that it is unacceptable, leaving you less likely to take on risk which might be necessary for growth and fulfillment
6. "is profoundly anti-intellectual", because students are encouraged more to acquire power and all that is necessary for it than cultivation of one's intellect, which requires such slothful indulgences as sitting in solitude, journaling, or even making time to have a relationship with a close friend
TL;DR for the TL;DR: elite schools' "real purpose is to reproduce the class system", instead of to grow their students' minds.
I'll add that when I read Deresiewicz's article in the New Republic and then went to his talk on my undergrad institution's campus, his tone was markedly more bitter than it is here in 2008. I suppose the situation has not improved in his eyes.