In the 1970s one could own a house and raise a family on one job and still have "discretionary income". Now even with multiple jobs a family is one bad month away from being on the street. Standards of living have declined across the board to the point where the United States is a third world country punctuated by affluent cities, so pointing to strip malls surrounded by a landscape of economic devastation just makes you look kind of delusional.
The reason one income could support a family is not related to race.
It's related to how the tax code and inflation have shifted to where it takes two middle-income wage earners to do the same. There is also the "consumerism" that's taken root, where everyone has to have the latest model of everything to be fashionable. I didn't grow up with
Cable TV
A COLOR TV
A TV in every room
A phone in every room
wireless phones
PCs
WiFi
The Interwebs
flat panel TVs and monitors
Refrigerators that do more than keep food from spoiling
15 appliances in the kitchen
5 appliances for hygiene
Pizza delivery
Color Laser Printers
FAX machines
More clothes than I can wear in a month
Air beds that adjust for each sleeper's comfort
Cars and trucks with digital music, 8 speakers, massive woofers, backup cameras, power inverters, etc.
and the list goes on.
If you compared your "needs" against your "can live without" expenses today, you'd probably still be able to support a family on one income. I did it for 20 years, putting 2 girls through college on my own -- something that wasn't an option for anyone in my income bracket in the 70s.