I recently read an article by Steve Sailer that reminded me about something I have been puzzled by for a long time. Relevant paragraphs:

If intellectuals could afford to have a lot of children, we might live in a world where they could sell enough heavyweight books to afford to have a lot of children. But we don’t.

So what should policy be?

In a recent article in the Boston Review, Heckman began, “The accident of birth is a principal source of inequality in America today,” then went on to endorse the usual expensive “interventions” in poor families. Should we perhaps instead strive for a country with fewer accidental births?

All of Heckman’s data suggest that we should aim for fewer—but better—poor children. Encourage poor people to conscientiously concentrate their scant parental resources on one child rather than three or six.

The government has had a policy of dissuading teen births, which have indeed been declining. Why not try to similarly investigate ways to slow down the rate at which impoverished unwed mothers reproduce? For example, why not invest in R&D for better, easier-to-use long-term contraceptives? The FDA’s approval of an injection contraceptive in 1992 appears to have helped bring about both fewer teen births and fewer abortions. Wouldn’t continued improvement—and, just as importantly, continued encouragement of contraceptive use—be a win-win strategy for all of us?

Poor people having fewer children means that the children have more resources available per capita making the children better off. Rich people having more children actually increases equality in society since it reduces the per capita resource advantage their children have. Rich people giving to their children is also one of the few cases where the redistribution of wealth doesn't reduce incentives for wealth creation. Rich people care about their children too.

Since programs aimed at reducing teen pregnancy rates do seem to have had some effect, we known something like this is possible without being horrible to the potential parents it targets.

Yet a policy of "poor people should have fewer children, rich people more" sounds heartless despite increasing general welfare both by making poor children better off and by reducing the privilege of rich children thus increasing equality which we seem to think is ceteris paribus a good thing.

Why is that?

Edit: To test the source of the reader's intuiton (assuming he shares it with me), I encourage the consideration of two interesting scenarios that may depart from reality.