The classic Chinese American food that was so prevalent was bastardized Southern Chinese cuisine brought over by mostly Hong Kong immigrants seeking the American Dream. It's struggle food. This was back when the US seemed like a land of dreams, leaps and bounds over everyone else, and no one in their right mind would move into closed Communist China (nor could their population move out).
Well, obviously, things have changed. The US has declined, the world's perception of it alongside it. Hong Kong was reunited with its commie motherland, and the motherland has gotten fat rich. If there are new generations of Hong Kong youngsters looking to make it big, they're going up north to the big cities that have become capitalist paradises, not across the pond anymore. Sad times.
I too remember when my dad would take us around to different small towns back when I lived in the US, and we'd encounter at least one single Chinese restaurant, usually a buffet, in nearly every single town. Guess those days are over.