There’s a famous satiric piece by an Afrikaaner journalist or politican where he apologizes to black South Africans for the white settlers who introduced them to smelting metal ore, wheels, combustion engines, electricity, running water, sanitation, and modern medicine. The same “apology” is due to American Indians from white Americans (North and South). Even their most advanced cultures, e.g. the Maya and Inca, never figured out how to work with metals (other than soft gold) and relied on volcanic glass for knives and swords.
They can also start picking from amongst their families and neighbors who they'll slay in human sacrifices.