In the article men are making fun of a woman. Here on HN startups are making fun of lifestyle businesses. On r/programming Scala developers are making fun of Java developers. On imgur people are making fun of 9gag. The internet is making fun of Bieber fans. Bieber fans are making fun of old people. Old people make fun of young people. Young people make fun of old people.
People poke fun at each other. It's how we establish groups. It's how we operate. We pick a trait and converge around it, as soon as we see a member of the species who does not have that trait, we make fun of them and maybe, just maybe, we eventually let them join the group.
If you want to fight sexism, go to a country that hasn't given women the vote, or women are still treated as property. that's sexism.