Not disagreeing with your main message, but it always irks me when people use dollar for dollar income comparisons across major geographic and national borders. Sure, Americans earn more than the overwhelming majority of the Earth's population. But if you compare the average cost of food, shelter, and transportation, let alone medicine across those locales, you'll quickly see that costs in the US, and even more so in major US cities, are far higher than almost anywhere else where people earn less. I'm sure Americans are by and large better off than most others, but not by anywhere near the margin that comparing nominal dollars makes you think.