I don't know if I'd call this overblown.
Remember, several of the personality disorders have an etiology in primitive defense mechanisms. These are college students--most of them ages 18-21.
The 18 year old cut off by the DSM to dx several personality disorders is IMHO too early a cut off. Several people don't mature for real until their mid to late 20s.
Several people in college act "out there" due to issues they dealt with growing up, and for the first time in college have the first oppurtunities to redefine themselves.
IF you take a look at the movie Trainspotting, it parallels several people in their youth. OK, yeah most people in college aren't heroine addicts, but it shows how several people in that age do things just for fun without thinking of the consequences. Then all of a sudden--after a few years of this they wake up & realize they need to be "normal" or they're going to go down a dark path during their lives.
How many of those girls in "Girls Gone Wild" have borderline or histrionic disorder?
I can think of a lot of my college buddies who had some Cluster B traits while 18-21 that they grew out of in their mid 20s. Heck I can think of a few things about myself that I out grew.
And IMHO, psychiatry (& usually medication) really isn't needed for personality disorders unless they are an on extreme where someone is going to directly hurt themselves or others. I do think though that someone with a personality disorder should seek some type of self help or counseling, though I also think almost anyone, even someone with a GAF >90 could benefit from that because counseling when things are going right in your life can keep them that way & perfect on top of what's already working.
My current health insurance allows me to go to a counselor for $15 an hour. I'm not going to one, but the idea of having some guy have to listen to my rants & try to analyze me, for $15 an hour, and maybe find something that can give me a little more insight--heck that sounds like it'd be worth a few tries just to see what happens.