While Tokaguwa and Chuck Day make somewhat valid points, the real reason is "coddling".
The "Greatest Generation" had to struggle to survive both the Great Depression and WWII (Quite a few did not make it through either.) I sit back in amazement of what my father went through just growing up in the Great Depression as one of three children to a widowed mother.
Human beings have to go through hardship, struggles, and deprivation to come out the other side better people. The parents of the 50's, 60's and into the 70's had been through Hell growing up. They didn't want their kids to have to suffer the way they did. So we ended up with Spoiled Brat Generation of the 60's and 70's and the Even Worse Spoiled Brats of the 80's and 90's. Followed by the Millennials, who simply take the cake.
American kids (for the most part) have had everything handed to them on a platter (Silver in most cases.) There is no hardship, there is no suffering. Anyone who is the parent of teenage girls understands this. In the absence of real struggle and hardship, teenage girls create "Drama", in 99.999999999% of the instances, the reason for tears, screaming, etc. is over perceived slights, and suo shee (there are nuances of meaning) incidents.
As an example, I coached my daughters softball teams, each year we had a draft. Her Sophomore year, I drafted her team and when I got home she asked to see the list. There was much screaming and gnashing of teeth (a garment might have been rendered also) and she went flying to her room in tears. I followed and asked what the problem was. She pointed to a name of my draft list and said "She said something mean about me in 4th grade." I said "Really?!?! Seriously?!?! THAT WAS 6 YEARS AGO, LET IT GO !!!!" But all that season, there was an unresolved hostility between the two that did nothing but damage team morale. What a bunch of gosa.
My son has the opportunity to spend a week on a working farm next summer. While I don't expect them to hook him up to a breadboard plow and have him plow the back forty, I do expect them to put him to work with typical farm chores so that he gains an appreciation of the daily work involved that supplies him his food.
Struggle and hardship, overcoming real challenges. That's what made America great.