That a classification exists does not imply everyone has to comply to it. Either you classify as female, or you classify as male, maybe both, maybe neither.

I don't know if you observe that too, but when i ride in the tram, i see individuals who neither pass as male or female. Not due to queerness, its because they have ambiguous bodies and don't perform their gender via their clothes or makeup or something like that. I'd argue that gender nonconformity was always there.