First of all, it is important to mention that individuals are responsible of caring about their descendants based on the values inculcated to them in family and community they belong to. So if the non-whites prefer to have several children detrimental to socio-economic comfort, the whites privilege socio-economic comfort. As a matter of proof, it is not common to see non-white with the deliberate choice of not having a child but among the white. So it is normal that the white decline.
I don’t have a PhD but you do. So, you are more likely to have access to an institution than I am. I would like to have a formal, moderated, and institutionally hosted debate with you.