Most of the vitriol is coming from the "cool" generation. It boils down to narcissism of small differences - the author is uncomfortable with the idea that he himself may be a "hipster" and so looks for all the things that are hip that he lacks. He then makes sure to publicly point out how hip these things are and how he lacks them.

I myself have been guilty of this but I eventually realized my own hypocrisy and just stopped caring about it. I'm a cool twenty-something techno-hipster - not because I want to be so much as because that's who I am.