Hipster-hate strikes me as just another thinly veiled form of bullying, and it's interesting to see how readily internet nerds - the people who are disproportionately to have been bullied in the past - engage in it. Look! He's different! Let's make assumptions about his motivations and get him! It's also interesting to see how many times Reddit (and other communities) fly into a rage-fest because of lack of context,…
On top of it, geek culture is a hipster culture. Oh you listen to obscure geeky bands and wear comic/anime t-shirts all the time? You purposely disengage from mainstream society? You're overly critical of the status quo and only socialize with people exactly like you? Gee, that sounds like the guy you're criticizing.
It is most often upper-middle kids (generally white) adopting and gentrifying sub-cultures and then abandoning them when all of the cool has been drained out. What is left becomes fodder for "ironic" mockery.
That is what the author never thinks of addressing. What he boils down to "they hate me because they think I want attention" isn't because he wants attention, it is because he has taken on the trappings of a group who devour other groups.