Fun, sparkly, casual gender nonconformity is awesome and wonderful, but it's also not the only type. Gender nonconformity can be serious, and it should have a respected place in society.
It's not inappropriate for a man to wear a dress to a business meeting. It's not inappropriate for a woman to wear a three-piece suit to a funeral. It's not inappropriate for someone to dress androgynous for an interview. Gender nonconformity is, for many people, just a part of expression. It's not just a performance or a fun weekend thing (although, again, that's good too)!
If gender nonconformity is only viewed as "casual", and is still punished in professional spaces for being "inappropriate", trans, genderqueer and gender nonconforming people will never be free. If you only treat gender nonconformity with respect in drag bars and pride festivals, you don't actually respect gender nonconformity.