I blame air-conditioning and television for this.
In my childhood home, alongside the Platte River of Nebraska, we lived in an enormous house with an enormous front porch. The town was about 3,000 people. For reasons I do not know, and there is no longer anyone around to illuminate me, we never had a television set; thousands and thousands of books, and lots of radios, but no television.
On summer evenings, one or both of my parents would sit down on the steps of this front porch after supper (no chairs; everyone sat on the steps). There were lots and lots of people walking around, driving around. Just about everybody came over to sit on the steps with the parents, chitchatting about everything under the sun. This would go on until after dark, my bedtime. I can't remember when there were less than, oh, 8-10 people every evening.
And then during the winter, every Sunday between Thanksgiving and New Year's Day, the parents hosted an "open house;" no specific reason, no invitation, come as one wished to come. It was a good thing that was a big house, and my parents were big on Christmas (more the religious side of it than the Santa Claus junk).
In my adolescent home in the Sandhills of Nebraska, the house was brand-new and air-conditioned. There was a front porch, but who wanted to sit outside on the front porch in the heat? Also, neighbors were few-and-far between, meaning nobody was out and about, especially not simply walking by.
I think air-conditioning and television did it.
