Is it somehow a problem that the sentence refers to a male collaborator? Maybe the author imagined a male person, or himself?

the explanation makes sense for people of all genders

The explanation makes perfect sense with any gender. Nobody will think "oh no the collaborator cannot be a woman because this text said his, I must find another version-control system which women can use too".

Is it somehow a problem that the sentence refers to a male collaborator? Maybe the author imagined a male person, or himself?

I think there's no problem referring to a male collaborator, but when doing so using 'they' (which includes all), it avoids reinforcing the stereotype that programmers are males.

See also: Nonsexist language (TLDR: please take requests like this one seriously)

We tried to make our gendering at least evenly distributed, and it looks like we succeeded in that; there are exactly four examples with a male character and four with a female. Of course, this was in 2014, before I knew as much about gender as I do now.

I'd totally merge a PR that improves the text in this way. Probably when the person being referred to doesn't have a name, we should use a they/them pronoun, and perhaps we change one of our named characters to a they/them as well? @hidde do you want to do that here?

@ben Many thanks for context, was not aware these characters were distributed 50/5, that's great! Change one of the named characters to they and use they / them whenever a character is unnamed. Should I start a new PR for that?

Should I start a new PR for that?

No need for that, you can just push more commits to this branch and we'll review them all at once.

I found one more instance of an unnamed character, and have changed “his” to “their”. Given there are only two named characters, I think we may just leave them gendered for now?

@ben From my side, this PR is ready for review.

I like it, this is definitely a good step. Thanks!