I would say some of the students in the article probably aren't SV material - "They’d begun studying computer science in college"? So you've been involved with computers for 4 whole years and you think you're qualified for a top tier job? I'm sure not all of the students only started in college - I'm also not naive enough to think there isn't prejudice in SV, but didn't start until college...
People of lower economic circumstances may not have had access to computers prior to college.
In 2010? This article is supposed to be about US, not a third-world country, right?