Bratty nerdboy wants to be girl
These kinds of outfits were for elite men back in those days… sign of status. Until it became "unpopular" for whatever reason.
For example… the poor making fun of the way the rich dressed. When that happened… style would change… and the past styles would become popular only for females.
Because wearing what you were being made fun of for wearing… lowered your perceived status. This is where men became compared to females for wearing the very same things they used to wear before it "went out of style" (only acceptable for women… think bell bottoms).