I've got a fair amount of code on GitHub and on my website, but judging from my most recent job search, hardly anybody ever looks at it. And it certainly doesn't seem like it does anything to get you through the first sourcer/recruiter hiring layer, which almost entirely consists of people who are not engineers.

On the other hand at the last job where I was on the selection/interviewing side of things (somewhat peripherally) I did look at GitHub projects.