That's not the point I was trying to make at all. The measure I was talking about is not a comparison to other nations, it's a snapshot of income/wealth distribution within a nation and how it changes over time. My point was that there ought to be very few rich people, and very few poor people, and the bulk of the people should be in the middle. This is the trend that has been occuring throughout the last few centuries, as middle classes grow explosively, upper classes increase slowly and lower classes get proportionally smaller. I have never advocated that everyone should "give according to his ability, and receive according to his needs", or that everyone own or earn exactly the same as everyone else. Not even the Soviets preached that, although the Maoists did. They eventually wised up.

Both the historical trend since ancient times as well as the generally recognized prosperous states in the world display a transfer of wealth towards the middle class, so that the number of very rich and very poor are small, and the bulk of the population is in control of most of the wealth. This is also the trend noticed in countries undergoing successful economic development, such as India and China. This is in line with the idea that if those talents (including sheer luck) which lead to economic success are normally distributed in the population, then the wealth should be distributed in the same way. I believe a fair economic system, a true free market, would produce this effect. If it isn't, then some other factor besides skill, talent, ambition and hard work is at play.

In ancient times, there was a tiny, fabulously rich aristocracy, a slightly larger craftsman/merchant class and an enormous peasant/slave class.
In general, the poorer you were, the more there were of you. In those days that was considered the way things ought to be, especially by the aristocracy. Today the trend is for the middle classes to be the dominant, in both numbers (height of curve) and in wealth controlled (area under the curve). Of course, no country has achieved the theoretically perfect Gaussian balance, but the trends should be headed in that direction. When they start going back the other way, towards a medieval distribution, the economic system is not doing its job, no matter what the GDP is or how many millionaires you're producing.

Perhaps you could turn your formidable research skills into locating some
wealth distribution graphs, number of people on the Y axis, income/wealth on the X axis, for several representative countries, or even better (that would be comparing apples and oranges), normalized histograms of US income distribution over the last half century or so. I'd be curious, with the great increase of wealth over the last few decades, to see which way the trends are going.

As a world, I suspect we have a long way to go. The site you linked me to said the following:

"A study found that the richest 2% own more than half of global household assets. Despite this, the distribution has been changing quite rapidly in the direction of greater concentration of wealth."

I be curious to see if the US is going against this global trend.