I generally agree that it matters more what you've actually done or created, not what you say on a resume.

But specifically when it comes to asking for the Github url (or the like): that assumes that the code they have worked on is open source. There are plenty of good hires out there that may not have participated in open source but still have plenty of code they've created. I think asking for a public repo is too heavily weighted towards open-source wonks.

I'm content asking the candidate to point me to something they've created. I work on webapps so presumably for the candidate that would be a public facing website. And then i study it. And then I grill them hard on the details of their implementation.