I don't think a github profile (or any specific activity therein) should be a prerequisite for being considered a 'serious developer'.
replyI am of the same idea. Requiring online, public repositories, specifically in GitHub, doesn't cover all developers. It covers many of them nowadays, so there's that.
replyYeah, it strikes me as a very... Silicon-Valley-brained view of software development.
replyFor example, I'm sure there's a scary-talented engineer working on fluid simulation algorithms for a major aerospace manufacturer, and they would be fired if their work-product ever left the corporate VPN. Meanwhile, their personal stuff is in a self-hosted solution.