If you’re planning to forego reproduction, I offer you my wholehearted thanks for making life easier for my descendants.

reproduction is fine, its just when families are having 5-6 children still, or when a human can only give love to a child if it is 'their' blood. Also in 1970 World pop was 3.6B, a much more sustainable number if everyones going to live a modern lifestyle with high consumption needs.

Yup. That was the whole plot of the book Inferno.