Cherrybim, you have to believe it to do it. Unfortunately, the most insistent of people who feel they are right and have the right to impose their beliefs on others, have a tendency to push others away rather than draw them closer. So instead of impressing them with their midos and their mussar they push them away with their “bad midos” and “harsh mussar”. You catch more bees with honey than with vinegar. So those who have vinegar dripping from their lips are going to push others away with the bad taste that emanate from their lips. The tznius police are not helping in Eretz Yisroel and it is not going to help here either.
The only way to change the attitude of tznius is to be exemplary role models of midos and maasim tovim so that others would want to emulate you and be on our madreigah in all areas. You might only change one person at a time, but you will never know how that ripple effect will work out.