I am not in that market, but this seems implausible. My neighborhood is pretty prosperous, but I doubt that $400k/year is the standard. Yet kids do go off to daycare.
Yes, that’s the point they’re claiming: a median family cannot afford healthcare. Are there any figures in particular asserted by the article that you consider faulty, or merely the conclusion?
"Uh, excuse me. This ad for a payday loan company says the vast majority of households can't afford this thing that most households with children do, in fact, afford and pay for. Which figures do you dispute?"
Concluding something farcical and then asking people to debate it is silly and a waste of time. 400k is an extremely high household income. Childcare is a common expense for families with children. The claim that only extremely high income people can afford a common expense is wrong on its face and needs no further analysis.