Basically because both parents are generally working, and there is no one at home to give 24/7 wisdom, etc. Learning how to live is not something children are taught today. There is no one to teach them.
In addition, American values are driven by social status. It's not a good thing. I've just hauled my daughter lock, stock, and barrel out of hte USA. I begged her to resign her job early last year. It took her until June to do it. Now she is with me in Europe, and she is not going back.
She has tremendous health issues as a result of living in the USA.
I'm truly sorry about your son. I'm sure you will be a great support. I'm thinking of you.