Joseph and all you pepole who say tznius hasnt changed in the past 2000 years,
Tznius depends on what is considerd pritzusdick in the time and place were you are: 2000 yrs ago woman walked around barefoot or in sandels, you would probaly hold that is ossur today.
If there was a style that is accteptable to jewish woman today for arguments sake black stockings (this is not a real example) that started being worn specifcly by harlots and the like I think you would agree that it would be ossur for jewish woman to wear them even though it was fine before.
It also makes sense that the gedolim of today would write tshuvas saying its ossur to wear black stockings that would still be around after this style stopped being worn by harlots ect. and it wouldnt be pritzusdick or ossur anymore after it stopped being worn by harlots and the like because that is the only reason it was ossur in the first place.
so bkitzer tsnius depends on what is considerd pritsusdick in the goyishe world to the extent that it dosnt violate showing somthing that is an ervah (hair, elbows, knees ect.)
so if a womans elbows and knees are covered and you think that she is dressed to flashy or tight or that that she violates the spirit of the law (even if you can find some tsuva from 50 or 100 years ago when the entire world considerd this cheap looking that says its ossur) if it isnt considerd cheap nowadays your not liking it is just your opinion and taste.
so for a man to comment on it, is just a man saying what his taste in woman is wich is wrong, indecent and extremeley untsniusdick.