He was extremely savage but it's when they got to the mainland that things became Apocalyptic for the Aztecs empire was so Alien to Europeans especially with winged serpent gods there goal was to eradicate the culture destruction as what happened with the native peoples of north America because

They were nomadic or seasonal with clans and tribes there culture was less in stone so there was alot of cultural survival, but even today what's left of the Aztecs is unreadable as there is no The Rosetta Stone, even how they built there structures didn't survive.