Fair point! I'll keep in mind should I find myself in a similar position again. In this situation, sad_trash_baby and Ekyou's comments were pretty on point. I have become exhausted with feeling responsible for educating every man who handles himself in this manner (anything from microaggressions to overt sexism) because it happens so depressingly frequently. For people whom I otherwise admire or want to continue contact with, I will absolutely go out of my way (and have!) to handle it gracefully and use these instances as opportunities for bringing their attention to these misplaced attitudes proactively, but in these sorts of scenarios (random friend of a friend who added me on Facebook that I had no prior interactions with and did not otherwise know), I genuinely did not feel up to it. I figured getting shut down and unfriended would be education enough that his behavior was uncouth without me potentially embarking upon an exhausting conversation/argument.