The topic of our society's ongoing decline recently came up, and while I agree that most folks are far from behaving in a Godly manner and we all could probably use an improvement of our standards, I don' think this is a recent development.
Our's societies' behavior hasn't changed as much as you think:
The Bolter- Book Review
(caution- some passages would get an "R")
The history of dress, note in the French Revolution and Empire periods, women's garments were often translucent- yeah, see through. Note the low cut of the dresses at Napoleon's coronation.
History of Dress
I wish I could find a better reference. When I studied this subject in college, we learned that during various periods of time different body parts were considered more or less attractive and dress was designed to feature the desired part of the body. There were periods when the bosom was completely revealed and other times when sheer fabrics were used. So while today's fashions are immodest- no argument there, I don't think the desire of humans to act and dress immodestly is so far changed from the past. It's just that there's not a lot of focus on modesty and moral practices in most history classes so we assume what we don't know about must not have existed.
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