Their aspirations for themselves, but especially for their children, will seem completely out of reach unless the number of persons that are to benefit can be reduced. To provide adequate food, clothing, and shelter for a large family quickly becomes a symbol of wealth that only the rich can afford. This is not speculation in futurology. The evidence is widely available. Countries with a reasonably comfortable standard of living have low birth rates and small families.
Poor countries have high birth rates and large families.
An increase in the standard of living would also increase health because people will be able to afford medical care, which, in turn, would reduce the spread of epidemic diseases. And while individuals will be in better health and will be able to lead more active and productive lives, the state will be able to invest more of the increased tax revenue in public health infrastructure. The number of problems whose possibility of solution will be increased is too large to be dealt with here. Suffice it to mention the potential reduction of homelessness, of crime, of illiteracy, of infant mortality, etc. The evidence for the relationship between standard of living and these problems is already widely available.