This argument proves too much. A minimum-wage US worker in 2015 has a higher standard of living than the vast majority of all human parents who have ever lived,

This argument proves too much. A minimum-wage US worker in 2015 has a higher standard of living than the vast majority of all human parents who have ever lived, or even the majority of parents currently living on Earth. Are you saying that almost all human reproduction so far has been a mistake?