Yeah but they are not all in North America. China+India = more than 1/3rd of humans currently alive. Try walking on the side walk in Mumbai downtown area in the evening.
apparently you missed the “over time” qualifier in the article. Only about 20,000 standing population.
Apex predators always have a smaller population than their prey or famine and cannibalism are next.
Humans figured out a better way.
(And that circle is about 50% ocean)