Rich is better. Eartha Kitt said that long ago. No one has been able to improve on it. Most people KNOW mobility is real. We are reminded at every family wedding and at every family funeral.
Economic positions can change from year to year, decade to decade, or from generation to generation.
The only thing we all know for certain is that they DO change. Well, not everyone. The idea of a tastelessly rich and useless upper-class has enchanted academics and intellectuals for decades. The book detailed, in 800 intensely footnoted pages, what he called The American Plantation and the unrelenting power wielded by an unchanging oligarchy of extreme wealth. For Lundberg, there was a self-perpetuating Upper Class.