Youth culture represents the perfect human contradiction. When you are young, your particular generation influences the large culture enormously, but only for a short time.
Whether bobbysoxer, beatnik, hippie, emocore, Swiftie or whatever, there is a brief moment in history when your group of young people holds center stage in the culture. And then history moves on.
The cultural dominance you have in your youth is the most ephemeral of superpowers, gone before it has hardly begun. And yet youth culture itself is immortal.
Even in ancient times young people were making an impression. Just check out what Socrates said about the youth of his day, according to Plato.
Since then, the power of youth to make their presence felt has not diminished. I suspect it never will.