I think the key thing you're missing here is that they were talking about behavior as the number of flips goes to infinity. That long improbable upper end beco

I think the key thing you're missing here is that they were talking about behavior as the number of flips goes to infinity. That long improbable upper end becomes more and more improbable over time. As time goes to infinity, the probability of being in it goes to 0. With a finite population, everyone is ruined. I ran the same simulation as you. After 100 iterations, the richest one had $71. After another 1,000 iterations, the richest one had $78 (of a total $133). After another 10,000 iterations, the richest one had 10^-165 dollars. They were still an extreme outlier with 95% of the total wealth, but he had almost nothing.