No you don't understand, women are choosing to work instead of staying home.
Besides, a man would need to make $200k/yr for a woman to stay home. That sound possible to you? How many $200k/yr jobs out there?
Think it all comes down to goals.
If a couple wants a nice house, 2 cars, a family trip 1x or 2x/year, healthy savings and brokerage accounts etc., you need dual incomes.
If the couple is willing to penny pinch, then it might work with a single income unless the man makes bank. Gotta factor his salary BUT THEN.....health insurance when you go past the EO-tier is $$$$. Family coverage for hubby + wife + kids takes a big bite out of the single paycheck. Flip side is you save on daycare which can be $$$$ too. Ideal scenario is having grandma babysit some and then maybe a young multilingual female that can teach your kid French, Swahili, Spanish etc.