That is very true, but you also have to keep in mind the flip side of this. The people who know the most about a subject, including ourselves, are likely the ones who will be most biased about it.

Not saying that is exactly what happened in the NYT piece, but that is certainly feasible in situations like this. The first person who writes the article is the person who was on duty in the newsroom or its virtual equivalent when the news broke. They don't know the details or history of the greater issue, so they stick to reporting the facts. Later, journalists with more domain expertise rewrite and add to the story. Maybe in this instance they are already knowledgeable about Reddit's questionable history with sexism. They see a story about a sexist website deposing a female CEO who is a controversial figure in gender relations (for lack of a better term). Suddenly the story gets reframed with that in mind. The extra opinion is only added because they know more about the subject.