In the past hundred years there's been major, rapid technological and societal overhaul. So the time we live in is very different from our parents, which was very difference from their parents.
But historic periods gets clumped together in major multi-century periods where it's hard to imagine that A man born in 1200 AD is going to be so "out of touch" which his son born in 1230 AD.
But I have to imagine that at least to some degree, children grew apart from their parents. But how much? How many "back in my day"'s could there have been prior to, say, the 1800s? I suppose there was the renaissance that changed music, and there would have been friction there. But before that?
Something you may find interesting is this quote from Ancient Greece:
Our youth now love luxury. They have bad manners, contempt for authority; they show disrespect for their elders and love chatter in place of exercise; they no longer rise when elders enter the room; they contradict their parents, chatter before company; gobble up their food and tyrannise their teachers
Link 1 (has a NSFW (explicit ancient drawing/graffiti image) and Link 2.
That quote would surely show how there were perceived differences between generations going back more than two millennia, in which the elders of society have always seen the youth as detracting from the ways of civility and respect, luxuriating in the advances in society which their parents never had.
Edit: But that quote is a later paraphrasing of lines from Aristophanes' The Clouds, a comedy, which mentions in its lines areas relating to the topic of the elderly finding bad ways in the youth. http://classics.mit.edu/Aristophanes/clouds.html