The term "slave" encompasses a lot of wildly different kinds of unfree labor. The racialized system most people think of from transatlantic slavery is a very recent thing.

Nothing resembling that was widespread in precolumbian North America. The earliest similar systems I'm aware of took root in the 17th and 18th centuries, well into the early colonial period.

While it was (mostly?) unintentional, the biological warfare committed by Europeans makes for a different story than anything that happened before they arrived. The Americas weren't a paradise, but neither were they a slaughterhouse.