It might help with a better understanding if the term cost of living could be considered rather than just being rich. Here is a good site to consider the equation by state:
https://worldpopulationreview.com/state-rankings/cost-of-living-index-by-state
As you can see, the difference is broad. Hard to determine rich by intake as there is no intake with property, just worth. And it is considered an asset. So that right there changes the equation.
wy69
State is too broad a guage imho.
Urban and suburban living anywhere is a lot more expensive than rural living.
In large states there can be major differences between different parts of the state.
In addition, the cost of living changes radically depending on where you are in life.
This is a classic case of where raw numbers confuse rather than enlighten.