Assuming all humans and populations of humans are interchangeable parts. We are not. Not so much "race" - which is a fairly idiotic concept as it's applied -- but hereditarianism is very much a real thing. IQ equates with life outcomes and is highly heritable. How people migrate (or are forced to migrate) can help you understand a population and population differences. Nigerians who immigrate to the U.S. now do far better than populations that were brought over during chattel slavery. Likely those who were captured by their neighbors and sold to European slavers had to lose battles of some variety. Selection effect. There are also documented differences between native populations in regions. Things like the harsh winter hypothesis pose that harsher environments lead to higher IQs. Otherwise, why doesn't every country look like Japan? If we don't diagnose the real problems societal interventions will fail to help anyone in a lasting/meaningful way.