That is a normal income for U.S. families with kids old enough to be surveyed. When you start with teenage kids, you end up getting families that are in their 30s, 40s and even some 50s. Also you are often talking about some dual earning families.
Also, many of those kids are getting phones second hand from their parents.
But also, yes U.S. kids have new iPhones. You buy the phone with financing from the careers and the cost spread over two years is pretty small for a middle class U.S. family.
Financing, the evil genius, or is that stable genius. I have trouble with these things