Parenting is not about quid pro quo, improving his childrens livelihood is his investment.
Regardless, you know as well as me - once you walk down that path no one knows it better then yourself.
Context matters. By itself, I would agree with your sentiment. But in the context here, it sounds like you are saying "You should cut your own throat to 'invest' in your kids!" There are a lot of people who really believe things like that. I think it is very unhealthy for them as individuals and for the larger fabric of society.