Less efficient? No they aren’t strictly less efficient because they provide MUCH better quality of care.

To less children. Even if the area under the curve was the same (and I suspect that there very much are diminishing returns) they have a very negative effect on the Gini coefficient and that is a negative externality that should not be incentivised.

If your position is that people should not be compelled to contribute to overall society and the lifting of the boats of others, than there isn't enough alignment of values for a meaningful conversation.

It does offer a potential backdoor to UBI while also encouraging desirable outcomes -- increased birth rate for wanted children, more people willing to foster, optionality for women to enter workforce, etc.

I suspect there will be some fraud (I have 30 kids, wheee!) as well as foster/adoption abuse -- probably AZ's experiment with paying parents to home school would be instructive.

At the median: probably. At the tails: probably not.

However, they provide superior level of childcare.