A lot of people blame the schools. But the schools were in full commie mode even when I was in high school, and we never bought into the crap. In fact, we rebelled against it. Global warming has been a thing since the late 80's and who can forget the 70's when there were pronouncements everyday about how we were going to pollute ourselves to death by 2000 and the whole "limits to growth" mantra. Anybody remember acid rain? The movie "Soylent Green" is representative of this mentality. Yes, this has intensified somewhat. But there has not been a profound change in the schools since the mid 70's.
One explanation is the helicopter parenting. I was a "latch key" kid, as well as my entire generation. We learned to be comfortable being alone and having to work stuff out on our own. I, for one, liked it, especially when I became a teenager.
Today's kids have parents hovering over them like helicopters all the time. I think this is the biggest explanation for what we see today. Government is the surrogate parent for the helicopter parenting kids. Oh, then there's the bid about the participation trophies. We never had these when I was a kid.