Actually, if you look at their numbers (or the summary numbers provided by the top-voted comment), the statement "women on github are more competent than men" seems to be a result of selection bias rather than "one sex is better than the other".

It appears there are more than 150k men on github but less than 10k women. But if you look at real life, men don't out-number women 15-to-1, which seems to suggest programming on github draws in more men than women. I suggest that, whereas in addition to professional men, tons of boys will make a hobbyist account on github to leave inane comments on open-source projects, there are very few hobbyist girls that fall into this category; that is, a woman only makes an account on github if she is a professional in the industry.

Naturally, if you compare a group of professionals against a group of professionals + college-rockstar-ninja-guru-hackathon-"yeah, but is it optimized?" amateurs, the group of professionals without the baggage would be "better".

Anyway, that's my take on what the numbers say; maybe I'm wrong, in which case, I for one welcome our new female overlords; if they must put us all to death, may they do so with snu-snu