The Age of Enlightenment prized composure and disparaged human emotion. The Romantics countered, to hell with composure! As William Blake wrote, "those who restrain desire do so because there's is weak enough to restrain." A life of love needed no guiding hand. Lord Byron wrote, "love will find a way through paths where wolves fear to prey."

Three generations later the pendulum swung back. The Dark Romantics underscored human fallibility. The Realists derided Romantic values and urged a return to everyday concerns and simplicity. Victorian culture prized moral strictness and Charles Darwin wrote, “the highest possible stage in moral culture is when we recognize that we ought to control our thoughts.”

Then the pendulum swung again, culminating with the Roaring 20s, the rise of Flappers, drinking, spending, and (relative to the time prior) lots of sex. Americans valued optimism and prosperity.

That was until the Depression hit and war pulled us back to stricter social norms. Those too were repealed and replaced by 1970s "counter-culture," "if it feels good do it." That lasted till now, and many are suspecting that Gen Z is a reaction to Millenials. They've accepted the progress we've made but also reject the mistakes we've made. I won't mention surveys right now else this will become political, but basically every generation is a reaction to the one prior. And sometimes reactions take 2-3 generations, but it's always a cycle.