sacrilege-
if you are defining tznius as strictly what you wear, and how many inches you cover, then you are right.
But the correct definition of tznius is to focus on the internal, and to treat the external secondary. Tznius is a mindset, not a wordrobe.
The problem with our system today is that we spend so much time focusing on the details. If we would teach our students more about living a life of tznius, we wouldn’t have to spell out every little detail. They would be able to come to that on their own.