Wasn't "brony" supposed to have something to do with "bro pony" or something? I think "pegasister" is just a play on words, too, and we already use gender-specific terms in everyday life such as he, she, man, woman, miss, mister, sir, ma'am, etc, and often not playfully either. Bro is a term that usually refers to a male and is suggestive of gender in itself, but as the fandom has kaboomed to include so many people outside of the target age range now I don't see why any specific names for non-specific factions should be required instead of using one big, familiar umbrella term. Seems silly to fuss over either.