I did not read the article, but in my opinion, sentences as "inequality is sign of health" is nothing else than capitalistic propaganda.

There is no evidence in my opinion, that given, that common wealth all over the world has grown (what I even would doubt a little), that it is because of our capitalistic way of thinking and exploitation.

I agree, that some degree of inequality might be inevitable, but that degree of inequality we have today is ill in my opinion.

If (and I mean "if") common wealth has risen, than it might be more likely because of state of technology today. To what degree our capitalistic system does contribute to it is just unclear. Our world might be more wealthy without it. But nobody can prove either side, since we only have one world! And comparing roman times to our days today is just ill thinking.