Completely disingenuous to compare slavery in pre- and post-colonial NA, and it has been "discussed" in many publications despite what the review states. Similarly, while slavery has existed for millennia, and irrespective of efforts to rationalize its existence in the US because we weren't the first or 'everyone was doing it', the United States is alone in its distinction for effectively turning it into a national industry during that 'modern' era and the lengths it went to replace/maintain a labor force coincident with the systematic annihilation of indigenous peoples.
Little about the practice of slavery as initiated by Columbus and his son has precedence either in terms of scale or investment, and certainly not during or after that era in history. One could also argue that genocide was practiced before the Nazis distinguished themselves by surpassing their predecessors, although I've never seen any attribution for the practice enjoying "popular acceptance". (Guess nobody bothered to interview the victims.)
Reviewer also refers to slavery in the past tense. That would come as news to the UN and a number of NGOs still toiling to eliminate it. Hope the book recounts the reality better than the review.