Because the byline wasn't easy to find on the device I read it on, and the possibility that someone might be offended by gender neutrality seemed far-fetched at the time.

> The author has the first name "John Carlos". Why not take an educated guess and use (gasp) gendered pronouns?

Because the text of the article could have been generated by a Turing machine with the pseudonym "John Carlos". And on the internet, nobody knows if you're a man, woman, dog, or sufficiently complicated state machine.

tl;dr: Non-gendered pronouns are inclusive and never inappropriate on the internet.