The truth is modesty ultimately lies in the heart and mind of any human being. A Muslim man or woman doesn't need laws imposed on them to be religious or to make practicing their religion easier for them. They should know when faced with the temptation and the possibility of committing sins, to look away and turn away, aka lower their gaze.
Likewise a modest human being, whatever be their perception of modesty, will be modest regardless of those around them. Telling others to be what your idea of modest is again makes no sense.