I can’t access the article but would be interested in how family wealth is preserved over 600 years! I’m going to guess that arranged marriages to others of similar stature, even cousins, and the headright system in which the oldest son inherits everything and the other siblings get nothing, are the central mechanisms.
I don’t think that would work so well in our country where divorce is allowed and laws protect all heirs equally. Both reforms tend to dissipate family wealth, as well as overextended lifestyles, debt, taxes and unfortunate business ventures. So, I can’t agree it’s a “lie”, since I’ve seen small and large fortunes go poof in my lifetime.