Imagine telling that to your young child every day and then wondering why your child has anxiety disorders and social problems. Part of being a responsible parent is shielding your children from the horrors of the world, so that they can develop in a stable and sane environment.
It can go the other way as well. My parents were helicopter parents that thought they were doing their best by shielding me "from the horrors of the world" and I suffer from related anxiety orders and social problems. I would've rather been exposed to more and had the ability to form my own opinions
I'm sure we can agree there is middle ground. I don't think instilling in them that they are just "waiting to die" unless they skip school and march in the streets counts as that middle ground.