To me it’s not even just that, it’s the fact that he said it to a) a total stranger who KNEW HER b) at a networking event without any concern for backlash, either for her or for himself. A person doesn’t do a thing like that if they consider the other party a possible threat to their own credibility, or if they consider them worthy of a modicum of professional courtesy. In other words, if they consider the other person a person.
Thank you for seeing things clearly. You are, unfortunately, rare.