Being poor and being smart are two different things. Poor people will constantly complain about their circumstances and blame others for their situation without truly seeking solutions, while smart people will try to seize every opportunity to overcome their difficulties.
Unfortunately, at least partially, but it's true. I think of the movie "idiocracy", does anyone remember this?
There, at the beginning of the film, they show how people with high education and good income carefully plan to conceive one child, while "others" acquire three or four children during this time.
At this point, just compare the birth rate in high-income countries and in poor countries. That's the way it is.