Exactly. Is that a bad thing?

I have two kids. My wife's salary almost doubles the first year and has to work less when we have a baby. As if our actions benefit anyone else. In turn, we have to submit the kid to an education program determined by the State, so I guess that's to ensure at least some benefit to society.

In the ideal free market circumstances, rational people would only procreate when the situation is manageable in itself. And I think it's a good thing.

Would it work though? Not automatically. Absolutely not. Poor people would become poorer by making tens of children, women would get more oppressed by men, the usual story. However, if we don't have nation states to impose some sort of status quo, then these problems would be solved in mere generations.