Some people exude tznius behavior, even if their wardrobe is less than tzanua.
Some people exude immodesty in actions even if they cover every inch.
I’m not sure which of those two are actually more tzanua. But in general, actions speak louder than words. [Not that it excuses the woman dressed improperly]
(And we can’t forget the orthodox women who wear burqas that fly in the face of what our rabbonim teach us. More covered is not always more halachically acceptable)