Anita Sarkeesian has a shaky yet valid claim to fame because she suffered a horrendous amount of harassment on the internet. Your opinions aren't held to the same standard of scrutiny when you're viewed as a victim of persecution, and that's why Anita has been able to get by saying this kind of stupid stuff without much criticism (outside of the internet).
Ironically, nobody would have cared about her if the internet didn't decide to try and 'stop her' by making death and rape threats on her website and on her Youtube videos. Instead, she would have received just about as much attention as every other SJW on Tumblr. You guys built a platform for her.