What about it?
It's pretty practical, I think. Two incomes aren't necessarily better than one. Two people working have the expense of childcare and more travel, and both share child-related constraints that limit their availability at work. With one parent at home, there's always childcare, there's half the travel, the working parent has more opportunity to thrive in their career, and the stay-at-home parent has the time and availability to provide from scratch.
My husband and I followed that model for years. We only have three children (we lost a fourth), but it was efficient. Now I have a job, and it's hardly worth it. We both think I should quit!