#1 Hording: If you've got a house full of crap, and you're deeply ashamed of it, you're not going to be having visitors over, ever. You're also not going to mention it on surveys.
We, the American public, have been collecting shit at a prodigious rate. Many of us pay rent for stuff that won't fit in our home. It's why the storage industry is so reliably profitable.
#2 Paranoia: Otis Toole[1] kidnapped then killed Adam Walsh. His father publicised his kidnapping, and fueled a moral panic that sent American parents deep into paranoia. Kids used to be free range, and were often collectively instructed to "go outside to play, and come inside when the street lights come on". After that event, we're afraid to even let them walk to a friends house a few doors over.
The end of the fairness rule, and the rise of fear based media like Fox news certainly didn't help in the rise of distrust.
[1] https://en.wikipedia.org/wiki/Ottis_Toole#Murder_of_Adam_Wal...