Does anyone still live with that kind of family-model? '2 people + kids / 2 incomes' is pretty much standard where I live, no one can afford otherwise -- not even the higher-earning income bracket.
Some of that is about how the tax system works in the US, too - the way that "married filing jointly" works was designed under the assumption that married women are homemakers, and so treating two-income families fairly wasn't a priority.
If one partner made enough to support the whole family and you had kids, then I imagine there are some families who would want a full-time parent caring for their kids vs relying on daycare/parents/nanny.
Ahh, I see... That's actually a rational argument in favour of it. I sometimes tend to take conditions on this side of the Atlantic for granted -- like 90 € / month [+reduction for lower-income parents] for daycare / Kindergarten.
When a 3-bedroom house can be had for $150,000 or less, you can get by on a single unimpressive income. It looks like that income could be just $40,000.
If you are higher earning, then you can go well beyond that. You can get acres of land, a dozen kids (my choice), a McMansion, and so on. This is how it is for my coworkers and I, living along the Florida coast.
If you have kids or living on a single income for 2 people, then it gets harder because presumably you'll want to find a more permanent living situation than renting a bedroom in a larger home with roommates or a small studio/1 bedroom.
My guess is that the existential crisis/breaking point happens for those in transition periods in their lives, the most notable those in their 20s/30s who have recently gotten married and thinking of having their first kid. At that point, if you haven't been fortunate enough to make enough to afford at least a small 2 bedroom in a good school area for $1.5m-$2m + school + daycare it isn't going to very sustainable to keep living here. Plus, many people want help from their parents to help raise their kids while they continue working, and unless you're in a situation where your parents are already living here that would be difficult to accommodate as well.