By and large I agree that none of these things have any relevance to software development. (And Github shouldn't be forced to tolerate anything, not sure where that came from.) But a couple edge cases may be relevant:

> Hate speech and discrimination

Gender as an entry field. People have a variety of views on this one. I imagine that the prevailing view is going to call certain other views "hate speech" no matter how politely expressed. It is up to Github if they want to take this stance on it, but it is understandably going to get them called the "PC Police" should it ever come up.

> Sexually explicit content

I understand not bringing this into discussions for no reason. But what if someone is developing a Leisure Suit Larry clone? I think implementing a NSFW warning for viewing a project is perfectly reasonable by almost anybody's standards. But disallowing it entirely will preclude such projects from Github. But again, totally understandable if Github decides that it's not the place for such things.