Economically productive as in

1. the economy is bigger and produces more goods. 2. much of those goods are distributed to the two-worker families. 3. a few bored minimum wage workers can look after a very large number of kids.

The quality of childcare is on average a function of how much you pay. The boutique ones have professionally trained staff that get more than minimal wage.

But what about the families that can't afford any but the most rundown centers, I hear you ask? Won't they be better off under the old system? You know, the one where the economy was 30% smaller due to halving the labour supply?

Perhaps they would be living poor but honest lives, perfectly happy in their squalid conditions and lack of medical care.