The existence of our civilization and the realization of its tremendous complexity, its reliance on so many people who have no personal connection or commitment to each other still doing what they have to do for all the others to get their work done. One of the reasons "Lord of the Flies" pissed me off so much was that it simply didn't ring true. If people were naturally that nasty, you'd never have gotten out of the caves, and certainly that whole "civilization" thing would never have caught on.
We hear about crimes, betrayals, and atrocities and are horrified by them PRECISELY BECAUSE THEY ARE THE EXCEPTION.
You don't see headlines, "Boy heeds parents, does homework with minimal argument", or "Man kisses wife, they resolve argument peacefully" because these are the norm. You don't see "Countries settle differences by quiet negotiation" because that's 99% of how it works.
We're living in an era of UNPRECEDENTED peace, with the vast majority of people not involved in war, with lifespans increasing and living conditions improving slowly (or not so slowly) in most places.
The crime rate is drastically down from what it was some years ago -- lower in the USA than it's been since the early 1960s.
People PERCEIVE things as being all so horrible because that's what gets news, that's what sells papers, gets views online, etc.
But the perception is 100% wrong.