That isn't true in my experience, though sqad, although I know it is a cliche that every generation doesn't really understand the next.
Discipline in previous years was often equated to violence- and that clearly hasn't worked!
But all generations deal with different things in different ways.... I don't pretend to agree with or understand everything my children follow... but they are good, respectful people, as are all their friends.
I also, in spite of working with all colours, religions etc. etc, have never yet met a Muslim, say, that doesn't eat bacon or drink alcohol. People rely too much on media hype imo.