Well, no surprises here!
The Wealthy countries rely on savings to see them through rainy days and retirement, whilst less wealthy countries rely on maxing out on children.
Does this matter? I would say it matters to everyone. Wealthy countries will have more markets for their products and services, and less wealthy countries will become even more destitute and corrupt. The result will be more economic migration from the less wealthy to the wealthy countries and then eventually wars over resources!
Just as well I expect to be 6 feet under well before 2050.