The fate of South America is not due to the failures of the local population... more "thanks" to decades of racist and/or anti-"communist" US foreign policy.
Admittedly, I did not fully understand the point the GP was trying to make with the Spain comparison.
This will be the case with space colonies too, I'm afraid. While it will be debatable why colonies perform worse than Earth, it will be apparent that the best course was to stay.
I don't know many fellow Americans that are of Norwegian descent but the US fairs better than the UK on lists of human development, happiness, and productivity. That has to mean something.