I’m nonbinary femme. I don’t like masculine or male terms. A few days ago, I was on a group chat with someone and they said “this guy” and used “he/him” pronouns, not knowing my gender. I, however, told them not to address me as a guy and that I preferred neutral terms but was fine with feminine terms as well.
No you’re not the asshole. That said if this is the first time it happened and/or the first time you’ve said something they aren’t the asshole either. If you have to say something again and they still don’t take the request then they become the biggest asshole but not until then. Ignorance can be fixed, being a belligerent jerk cannot as easily