Maybe, but another angle is that, in net terms, the world developed more as a whole thanks to the exploitation of the natural resources and the resultant, broader economic and technological development.
It has all contributed to the world we all now live in and benefit from. This obvious consideration seems to have escaped your consideration. Also, the slaves taken to the Americas may well have been better off than if they'd stayed in Africa or Arabia. Certainly their decendents have ended up better off, in basic economic, health and other terms.
The efforts and suffering of those who existed before us, in all their many forms, from primitive peoples, to renaissance geniuses, to those hanged for taking a loaf, to African and other slaves, industrial wage slaves, indentured labourers, aristocrats, and so on... were not for nothing. Despite your very modern and over privileged, phony outrage.