States in the US vary in nominal GSP per capita by only 2x — from Mississippi at $35K to Delaware at $70K. In the EU, it ranges from Bulgaria at €6K to Ireland at €55K. (This excludes DC and Luxembourg, which are outliers in many ways.)
In fact, even Mississippi, the poorest US state, is wealthier than the EU average (€28K, about $31K)! Only the wealthiest EU countries are wealthier than Mississippi: Luxembourg, Ireland, Denmark, Sweden, Netherlands, United Kingdom, Austria, Finland, German, Belgium, France. And of those, only Luxembourg and Ireland have a higher GDP per capita than the US average.
So the EU member states vary economically far more than the states in the US do, and the US is more easily characterized as a uniformly "high income" region than the EU is.
Mississippi's GDP per capita being similar to that of France, Italy or Spain is really hard to reconcile with the fact that many of us would love to live in the latter countries and couldn't be paid to move to Mississippi.