Mass culture is educating people to a level which it wasn't possible before, pruning really bad examples, and suggesting attainable relationships with self and the world. Lead is maybe a big reason why it succeeds, but even before the 192x when the lead started, people and craziness were wide spread. What happened with the maturation of all the media channels is that old religious and religion-derived psychoses were pushed out of fashion and being yourself wasn't opposed by centuries old norms. Being creative is often correlated with suffering and we are actually happy right now.

I don't mean that we don't have problems and the concentration of wealth and power in the hands of a few is maybe causing part of the uniformity, but generally, we call them creative solutions, because they are aimed at uncomfortable problems.