That explains jealousy, not "suffering" as the upthread commenter put it. No, this is 100% irrational.
I mean, think about it: there have always been phenomenally wealthy people. If every billionaire in the US had their net worth cut by 50%, instantly, that would fix the "Gini index" you think we should be looking at.
But would their lifestyles change? Would anyone but the billionaires even notice? If you stop a person on the street and ask "Is it fair that Bill Gates is worth $50B dollars?", they're going to say "no", right? That's way too much money. Except, of course, that Gates is worth twice that and the number is something that you argue should be "fair".
No, it's not numbers. It's irrational delusion fed by fear and anger and click-chasing from everywhere across the media landscape. But. It's. Wrong. And someone needs to start telling people that.
Because at this point our shared delusion is causing a trade war that is going to make all of us (literally, all of humanity) poorer.