Yseribus: That’s median household income, not median individual income. The artisian hippie from Park Slope lives with his girlfriend, who also is earning an income, a dog and maybe one child. Their combined income for a tiny family puts them squarely in the middle class. The Satmar guy earns more than either him or his girlfriend, but not both combined. And his Rebbetzin is running a nursery in her home — of her own ten kids, which she isn’t formally paid for.
So, sure, the goy has a higher combined household income with their 1.2 children, but the guy in KJ has a higher individual income, which isn’t reflected in the household income stats you refer to.