I like hierarchies as an UI metaphor and I agree with you: github is a development tool. Unfortunately, it seems that the author confused his usual ux work with

I like hierarchies as an UI metaphor and I agree with you: github is a development tool. Unfortunately, it seems that the author confused his usual ux work with the one he was proposing for github. That said, hierarchies are dangerous because they hide stuff. It's clear that github's need reviewing.