At a national level, it’s hard to see how (assuming the country grows enough food and has other basic necessities) it is possible for the country to be “unable to afford” children, Baumol be damned.

There's never been a time in the history of mankind when there was greater abundance than now, but we suddenly cannot afford children anymore? Maybe we ought to task scientists with figuring out what precious secret to raising children mankind forgot when we were too preoccupied with discovering fire and electricity. Hopefully they left us some carving in a deer antler that will give us insight into their superior budgeting skills.

I'm sorry, but that's absolute nonsense.