Superstarism is a old tool and well documented (for those who read) tool of the rulers of courts to keep their entourage in check. In brief: be an abbedient lackey or lose the favour of the court. Because it misses the bottom percentiles overlooking, it overlooks them; as e.g. the French revolution shows, it may become untenable, for good reasons, at any moment.

The existence of opportunity is best proven not by looking at how high one might go, but at how many are left behind. And how, according to certain measures, they are in fact regressing.

This isn't really an argument against as much as a reason to be suspicious. It still can be a useful metric, it says something about social mobility. I'm unconvinced.

>it misses the bottom percentiles overlooking, it overlooks them; as e.g. the French revolution shows, it may become untenable, for good reasons, at any moment.

The French Revolution was precipitated by large scale starvation, conditions that the US is extremely far from. This is, ironically, a case of bias looking at successful revolution-- most revolutions historically aren't successful and certainly not to the extent the French Revolution was(influencing later revolutions and the political thought). Looking at recent revolutions across the Middle East and Africa in the past decade, most of them largely fizzle out when the ruling party pushes back with force. Even when everyone want a revolution, most people aren't willing to put their own life on the line for it. Not unless the alternative is worse-- bringing us back to the conditions that started the French Revolution