This thread actually answers the OP question of what's happening with the seeming increase in the number of untrained dogs, because around 80% of the comments are making excuses for antisocial behaviours that their dogs have.

I've trained my dog to not bark, to not chew, to not take any object for which he has not been previously permitted (baby toys for us namely), to walk at heel, and so on.

And guess what? he still exhibits behaviours that are antisocial, like imperfect recall and begging behaviours. And I'm damned if I'll make any kind of excuse for it: I am still training him to deal with these behaviours and I will continue to do so because I owe it to him.

If you do anything short of that then you are failing your dog, yourself and the people around you.

If you couldn't have guessed I'm also in favour of licensing for pets because, like many, I've encountered too many dogs at the extremes of antisocial behaviours to think that the average person can be trusted, through apathy or intent, to prevent their animal from harming children.