Terence McKenna lectured on this at length. Here are some apropos quotations:
"As a global civilization, we can no longer afford the luxury of an unconscious mind. When you can pull down the fusion processes that light the stars on the cities of your enemies, when you can sequence DNA, when you can map the heart of the atom, then it is entirely inappropriate to have an unconscious mind, because the power that is given onto you is a kind of god-like Promethean power. So how can we switch on the lights on our animal nature…? I think it is very simple: we have to de-condition ourselves from culture. We are sick, we require medical intervention… into what is a galloping, cancerous state of neurosis - the growth and spread of ego. Ego is like a calcareous growth in the psyche of human beings, and if it is not treated, it creates the kind of society that we have. A society based on hierarchy, male dominance, accumulation of physical goods,suppression of the weak by the strong… This is why the psychedelics are so socially sensitive, because they dissolve de-conditioning. Every culture is a scam. Every culture is a lie. A shell game, run by weasels, for the amusement of rubes. If you do not want to be a weasel or a rube, then you need to inform yourself of how the shell game works, and what lies beyond the carnival midway of civilized values. And the way to do that is to go back to the plants, to the original gnosis."
https://www.youtube.com/watch?v=_IO7pHD3X9M
"Culture is an effort to satisfy this weird desire human beings have to close off experience, to live with closure, to force closure. That is why cultural trips are so bizarre; why they don't make sense to anybody but the Witoto, or the Guaraní, or the Americans, or the Japanese. If you are not inside a culture, it seems crazy. Cultures do not make sense because they are not trying to make sense. What they are trying to do is produce closure, which then somehow makes a human being, who is living in the light of closure, a more manipulable, a more malleable, a lesser thing… The message coming back at all of us is: live without closure. That is the honest position given that you are some kind of a talking monkey, some kind of a primate, some kind of creature, on a planet, in an animal body,in a time and space. In the face of that, life without closure is the only kind of intellectual honesty there is. If you have to inoculate yourself against the various means of closure that are around,psychedelics do that. That is why they are so politically controversial and potent, because more than any other single act that you may voluntarily undertake, they pull the plug on the myth of cultural meaning."
Terence McKenna: Don't Believe/Follow/Consume/Watch: https://www.youtube.com/watch?v=kV1RC2zlymQ
Dissolving the egoistic boundaries of society (Terence McKenna): https://www.youtube.com/watch?v=J7sfZiRLqOE
I think the young execute on a unique position to see the culture of their elders and actively choose to fill spots where it could be improved for their own benefit and drop customs that are no longer worth it.
I don’t know if I believe this in general. Certainly we are happy to utterly change our lifestyles whenever a convenient new technology comes about. How much have smart phones or social media changed us culturally in the spans of a couple decades? If culture can change quickly over convenience, surely actual pain would drive it to change even faster. It seems that those “hard to change” cultural aspects are actually _useful_ in some way, and therefore they survive.
One thing I find fascinating about humans is that we are so compulsively cultural that we will actively propagate cultural practices that are harmful even to ourselves. When you are young, you absorb whatever culture is around you completely uncritically, and then you immediately turn around and start broadcasting to the next generation.
Cultural changes and evolves, of course, but it's really hard to uproot a norm or more once it's settled in, even if it's one that causes you personal pain.