What do you mean by "less developed" ? Those people have been with us on earth for the very same period of time as any other human. So they have been developing themselves culturally, economically, whatever-ally as much as any other human.
I can see the desire not to look down on others, but economic development isn’t measured in time as much as wealth accumulation. Wealth begets wealth too, so the wealthy countries today tend to be the winners of the industrial revolution (most of Western Europe and Japan which industrialized early).
What do you mean by "less developed" ? Those people have been with us on earth for the very same period of time as any other human. So they have been developing themselves culturally, economically, whatever-ally as much as any other human.