I have years and years of experience in software, I have a half dozen or more non-work projects I've contributed to or solely developed, some involving hundreds

I have years and years of experience in software, I have a half dozen or more non-work projects I've contributed to or solely developed, some involving hundreds of hours of dev work, most of them on github. None of those projects are public though. And I suspect a lot of other developers are in similar situations. Public contributions on github usually fall into one of two categories: contributions to big open source projects (rare) or pet projects of little substance (common). These are just some of the reasons why using github as a resume is extremely fraught with difficulty. If you're lucky then it works well, but chances are you won't be lucky.