It's not a new thing really.
I've a family member who's kids were at high school in the mid 90's and they were incredibly badly behaved, but they'd been pretty much allowed to do as they pleased from a young age, so to them it was the norm, and looking back they weren't the only parents that had DC with that type of behaviour, it seemed to have spread among the area where an amount of parents just didn't seem bothered.
Once they'd grown into young teenagers and started to bring the police to the door their parents took on a "what do you want me to do about it" stance.
Behaviour has carried on throughout their lives.
Now having DC of their own, multiple, ranging from 4-13 in age the pattern continues X 7, so it grows with each generation, none of them flinch at giving you the middle finger, saddest thing about it is the parents are happy to put pic's on social sites showing this, no shame, no embarrassment.
I wasn't often lost for words but it's now becoming a regular occurance everytime I hear of a person having lost their life at someone elses hands it leaves me speechless at how young those doing so are becoming.
I think there's no denying that we'll see more and more of it unless there's dramatic changes ahead.
I certainly don't blame society as a whole though, I for one can only be responsible for my DC and any put in my care.
You daren't pull another's DC up on there behaviour today, and I think some posts on MN have shown that.