It seems to me that before the young had this opportunity to decide for themselves (which, admittedly, can go a lot too far and is doing just this as regards the consumer aspect of 'youth culture') the alternative was not having any childhood at all, looking after the household and younger siblings, getting their first job at thirteen or even earlier than that, and being regarded as little 'grown-ups' in every way. Doesn't seem very desirable to me either.
Admittedly, both concepts are put as absolutes; in the real world, there are a lot of stages in between one extreme or the other, I suppose.
And, yes, Shambles, I tend to think it probably is inevitable that children to some extent reject the values, tastes and opinions of their parents while they are growing up and trying to find their own. If they don't, that may not be a good thing either, as I know from personal experience. - Susanne