That is part of the problem. But an even bigger reason that 'kids just don't listen to their parents anymore' is that more and more 'kids' simply don't care what their parents say or do.
I see this especially with children who were put in day care before they entered school.
Day care not only exposes children to truly awful behavior committed by other children --behavior they quickly learn to imitate.
More importantly, day care deprives both child and parents of the bonding that normally takes place when the pre-school child spends most of his time at home with momma ... rather than in a dreary institutional setting, where adult authority is either diffuse or non-existent.
The kid who doesn't bond --because he's spent most of his early life in day care-- doesn't much fear losing his parents' love and approval with his bad behavior.
I expect that may be so, although I thought that "bonding" took place mostly in the first year. But I guess some babies are at day care all day long, and maybe start going in that critical first year, because both parents have to work.
Another, related problem is presumably broken families, divorces and remarriages, and all that kind of pattern, so there is bonding that gets broken or betrayed. The step parents can be decent and well meaning, but it's not the same kind of reliable world for the child to grow up in.