Just adding a few things to this post based on discussion in comments:
*My point is not "everyone should want to live in cities!" just that while I get that raising children in an urban hellhole offers some different challenges, I don't get the idea that it's universally "more difficult."
*Urban hellhole living doesn't necessarily mean downtown skyscrapers, or being carless, or more generally lacking anything resembling suburban amenities. Supermarket and Target with large parking lot are near to me. Also, too, Walmart and Ikea.
*Yes schools are an issue that can trump everything else. I get that.