I'm sure a bucket full of your source code on bitbucket will serve the same purpose when interviewing. I'm on the job hunt and in interviewing with some YC startups we haven't really gotten to my github, since they more were interested in some of the closed-source projects I've done at other jobs. I think the overall point of the article is to be able to show people you can code rather than just list it as a bullet point in a document.