Your premise is that anyone having children at all is equivalent to unbounded population growth. If literally everyone stopped having children, humans would obviously become extinct.

Moreover, it is generally considered a sound principle that successful professionals should be encouraged to have children. Whatever combination of genes, knowledge and resources allowed them to become successful themselves is more likely to lead to a successful next generation. And high income earners are more likely to accept paying taxes to fund good schools and other programs for children if they have their own children to make use of them.