Poor article. Way to much generalization going on. Case in point is the reference to GW Bush. He gets a pass on his youthful indulgences and yet that's precisely what the author condemns many of the "hippies" for.
Drinking beer at a frat party and getting blown away is Plaid. Sitting in a ramshackle apartment and getting stoned while listening to Pink Floyd is Woodstock.
I think you are missing the point of this article. Both sides did stuff when they were young. It's what KIND of stuff they did.
There is also the matter of who has grown up, and who has not. I think a higher percentage of Plaids have grown up.