Agreed. I love arthouse films and have sod all interest in popular culture, but don't struggle with friendships, and, if I did, I wouldn't ascribe it to me being too edgy and off-kilter because, as you say, people with my interests aren't exactly rare.
(And LARPers always have mobs of fellow elf/Orc friends, otherwise there wouldn't be anyone to reenact the Battle of Helm's Deep with...)
I think that article is deeply silly, if only because the author seems to be mistaking a Hollywood confection of 'girl group' friendships for anything approaching reality. I've never seen The Golden Girls, but the characters in Sex and the City were a handy conceit to have a pool of different 'types' (the slut, the princess, the hardboiled careerist, and the self-indulgent narrator), while from what I remember about Bridesmaids, the whole point is that far from being a united 'girl group' Kristen Wiig's character has never met most of her supposed lifelong best friend's other bridesmaids, and develops an insane rivalry with one of them...? Hardly rosy.
People writing screenplays and novels write in either a single best friend or a small group, because it's easier than sketching in several completely unrelated friends or sets of friends, especially when the friends aren't the focus. I'm writing a novel where the heroine doesn't have close friends, only her sister, and I only wrote her sister in because part of the plot involves their mother dying, and I needed her to have someone to act against in the hospital. Bluntly, my focus is elsewhere, and I dont have space for my heroine to have an extensive social life!
The author seems to have failed to grasp this.