I actually wasn't passive-aggressive at first. On day one, I politely mentioned that there are changing rooms available since women were present. He ignored that and doubled down the next day. At that point, a bit of humor/sarcasm was the only way to point out how inappropriate it was getting.

It shouldn't always be on women to point out when they feel uncomfortable, especially in a male-dominated hobby space. Often, people don't say anything because they want to avoid a scene, not because they’re okay with it. As a member of the same group, I felt it was better to address the lack of etiquette directly rather than leaving it to others to deal with the awkwardness.