"I will instantly disregard any CV that doesn't have reference to a GitHub account"

Well bravo you. The problem with recruitment in our industry is not the candidates with no GitHub account, its the egomaniacal interviewers who waste no opportunity to turn any interview, in this case any application, into a passive-aggressive pissing contest.

Perhaps its acceptable for an interview to be adversarial, but I don't think any other industry matches the tech industry for the utter hostility of the interview process.