Hi, I'm Shiloh, the guy that made the original reddit post and medium article. After reading some comments, I clarified my statement on GitHub's role in the CS industry
Training our next generation on proprietary tools like GitHub isn't the way though. Understanding a VCS (i.e. Git, Mercurial, darcs, Pijul, etc.) is great skill and almost certainly a job requirement, but a specific platform? Its classification as “industry standard” could and should be debated as well.
It's not realistic to suggest people avoid GitHub with the kind of market dominance that GitHub has. I while I empathise with the sentiment learning GitHub is absolutely a tool that will help them get jobs in a way that Git alone won't.