Heck if you're talking about music, when swing bands emerged on the music scene in the early 1930's, parents were horrified and mortified to see their children dancing like animals in the aisles of concerts. At the time there were those who thought civilized society was on the verge of collapse. Then the swing dancers grew up to have children of their own...and much to their dismay, those kids became the 1st generation rock-n-rollers.
No doubt each generation ups the ante a little bit and tries to make their own mark. However getting back to the original topic of TV, I don't think the changes as to what is acceptable can be linked just to the passing of successive generations. It seems to be more a case of societal conditioning.