It's an empire. Empires are good at concentrating wealth by extracting it from their surroundings.

Personally I would absolutely not want to be a poor person in the US. High crime, police violence, abusive work conditions, random shooters, health care bankruptcy, Fentanyl being pushed by medical professionals, zero Covid protections - it's a dystopian horror show.

This may surprise you, but there are locations around the world with much lower GDP and much happier people.