Consider the early 20th century. Some ostensibly irrelevant political figure was assassinated which rapidly spiraled into the "war to end all wars" in which about 20 million people were killed, in a world population of 1.7 billion - so more than 1% of people. In relatively short order this led to the Great Depression in which over 10 years the global economy collapsed leading to mass suicide, starvation, and disorder.

And we were just warming up. After that it turns out that the war to end all wars was just the pregame show. An eccentric vegetarian artist with a knack for riling up crowds decided to declare a literal genocidal war on the world, and for some time it looked very much like he was going to win. It only ended after another 80 million deaths (about 3% of the world population this time), the deployment of nuclear weapons, and countless war crimes.

And then? Decades of people got to live in the great times where every day there was a real and legitimate concern of imminent nuclear war (which did nearly blast off multiple times) to the point that nuclear drills were a part of the classroom, and people building their own nuclear doomsday bunkers was not only not eccentric but just plain ole pragmatism.

The point of this is not just to emphasize that the past was unimaginably and exponentially worse than the present in every imaginable way, but rather that there was no widespread mental health collapse. And there was no "shielding" kids from anything, when the world was literally burning in front of their eyes. So clearly something has changed, and it's not just that things have just gotten bad or that people are now uniquely aware of that. I have my own hypothesis, but this post is already too long. I'll conclude with a song which this post reminded me of:

Song: https://www.youtube.com/watch?v=eFTLKWw542g

Lyrics: https://www.musixmatch.com/lyrics/Billy-Joel/We-Didn-t-Start...

Meaning: https://en.wikipedia.org/wiki/We_Didn%27t_Start_the_Fire#His...