David Rockefeller made the list at number 605 with $3.3 billion. There are Saudis and folks from the United Arab Emirates on the list. Many of the old money people that you are talking about are worth hundreds of millions individually but not the one thousand million it takes to be a billionaire.
Here’s a link to the complete list:
https://www.forbes.com/billionaires/list/14/#version:realtime
I gave up at about number 625 and I was still in the $3 billion range!
For example, Queen Elizabeth’s net worth is estimated at $550 million.
Thanks again