SMy thoughts on this sensitive issue:
1. No one ever likes being told off for doing something wrong.
2. Enforcing keeping of Torah is not a Jewish approach, except with certain averos which the halacha dictates one should protest. E.g. Talking during chazoras hashatz.
3. Notwithstanding the above, women who dress nontzniusly are being selfish, by directly challenging the frumkeit of frum men. I refer to women who dress in a manner that is unanimously considered not tznius. E.g. Skirts above the knee.
4. Is it not unfair and wrong that they can get away with such selfish behavior in public?