Well I don't know how much my own opinion would be accepted. However I have lived longer than most of you. I have seen all the phases of fashion, decorum, dance, and music. Behavior, both sexual, and social, come and go. All I can say is, they are always new to the generation at hand, and irritating to most of the generations that have gone before.
I don't know how much you know about the fifties, when I was growing up. However as has been mentioned here, Rock, "and Roll," was just emerging. There were lots and lots of older people who thought it was going to be the downfall of the entire culture. Specially when Elvis came along and gyrated his hips in such a suggestive fashion. He was photographed from the waist up in most of his appearances, and given a very large birth by the established radio and music industry. I look back on it now and want to cry foul to those people that now call him "The King." I wonder how many of those folks are some of the converts, that first deplored him. Next big jump was the Beatles of the 60s, with their horrendous long hair. lol. People were outraged by that hairstyle, and the Stones, welll don't get me started. People thought that they were devils. May I regress a bit, the fifties were the place where low riding pants became fashion. Not to the degree that they are nowdays, but no one back then were skate boarders, "boarders," either. There was no such thing. But I myself wore the Levis, which were the mainstay for jeans. " Lowered," to much the same level as low rise jeans now come. Back then it was totally scandalous to most older folks too. But then the level was not the reason that it became popular now. It had nothing to do with sport, and by association juvenile gangs, etc. it was just cool. So to speak.
I have to say, having children who were the first group to wear long hair,,(which drove my husband up the tree.) I didn't mind it myself. Then the pants thing, because they too were the first to have skateboards as well. It is just much easier to manuver on one of those things with baggy pants. Then there was the striped, and patterned pants of that time, with the huge bell bottoms, as you can find on many of the singing groups back then. That was very odd. But hugely popular. The bigger the bell the cooler the outfit. Of course like all things, it was finally tempered to the now very acceptable "boot cut jeans."
I know that I am not covering all the ups and downs, and in and out of fashion, of accepted behavior, or music. However I can say this much. It has one thing in common. Change! It is keeping the generations separated, and unique for the time they are pre pubescent, and teenage. Usually moderating in the twenties to thirties. Of course as I mentioned there are certain aspects of each thing that is "changed to fit." Then forever becoming a part of the general use and vernacular.
I personally think it is heathy. It allows for each succeeding generation to establish its own identity. While at the same time keeping them for the most part just a tad off of the center, allowing them to fall back in line with the general accepted behavior. Not leaving too much of themselves out in the cold. Sooner or later as I say, usually in the twenties at the latest, they realize it is not a thing that they have further need of. They are independent, proud, and ready to make their generations next mark on the world. In short its a harmless way for all concerned to come to terms with the way the different generations will fit into the whole. A bit old, a bit new, a bit weird, but a cohesive thing. It only makes a richer soup. If you will.