I agree that South and Central American civilizations do not get the respect that they deserve. Egypt and Mesopotamia had metal technology; the Americas did not. They were stone age. They didn't even have pack animals.
People wonder how the Egyptians built their pyramids? Try making larger, more complex structures without metal tools, horses, camels, or the wheel. They did it with stone knives and bearskins, literally. For them to do what they did with the technology that they had is truly amazing.
Except for the Old Copper Culture in the Great Lakes area.