The Spanish abused the natives in all sorts of horrifying ways. That is why Las Casas suggested that it would be more humane for them to import African slaves.
The conquest entailed the death of at least 75% of the native population, mostly through disease but also through maltreatment and violence.
The Aztecs were more modern than the Spanish in a number of respects. Their agriculture was much better. Tenochtitlan was a larger, more impressive and better designed city than any in Western Europe. Aztec art is also very impressive.
The Aztecs and the Spanish were both brutal civilizations. The Spanish were plenty barbaric - especially once they expelled the Jews and Muslims.
“The progenitors [you mean progeny] of the Aztecs should be greatful for Cortez and the Catholic Church, because it wasn’t long after Cortez that the Catholic Church converted 9 million Aztecs to Christianity...”
The Spanish method of saving souls was not a gentle, kind process, by the way. They would have been much better off if the Spanish hadn’t been so concerned.
The point is, the history of Mexico is not some black and white lesson where the good Europeans saved the ignorant brute natives from themselves.
Actually it is. Practically every case of civilization beginning in a particular country started with some superior (and many times very violent) invading foreign army going in and destroying the existing culture and nation. It happened to my ancestors (when the Romans came in), and it probably happened to yours. I'll state unequivocally that the best thing to ever happen to Mexico was when the Spaniards came in and destroyed the Aztec civilization. One brutal modern culture uprooting a brutal primitive one.
But as brutal as the Spaniards were, they were a huge improvement over the Aztecs. Because they represented western civilization with began the still ongoing journey of Mexico into the modern world. I'm not making excuses (or maybe I am) for the cruelties exhibited by the Spaniards. But it was necessary for Mexico to jettison the primitive, bloody, and anti-modern ways of the Aztecs.
The Spanish were often very brutal. However, wasn't their policy not so much forcing Christianity (of the Roman Catholic variety) on the Amerindians, but rather forcing them to stop being pagans (the Aztecs, Maya, and other tribes in the region did have very savage religious practices)?
The book, 1491, states that some estimates of the pan-American death toll caused mainly from diseases transmitted from Europeans could have been higher than 90%.
Tenochtitlan was larger (in population) than the cities of Europe, with the potential exception of Constantinople. It was also constructed by the Aztecs in a shallow lakes as a collection of manmade islands connected to the mainland by some causeways. Pretty impressive.
It seems that there is the idea that if one civilization is the most advanced in one area, it must be the most advanced in all areas, probably because for the last couple of centuries or so the Western civilization has been on top basically across the board. However, as you point out, that often isn't the case. Tenochtitlan was grand, the Maya had a more accurate calendar than Europe and advanced maths, etc. Some of the Iroquois had what could be considered advanced medicine at that time.
Personally of the opinion that Spanish and Portuguese subjugation by the Muslim Moors for around half a millennium caused for some Islamic traits to rub off on them--chiefly the violence. Notably, the English and particularly the French (also Roman Catholics) didn't pressure the surrounding natives in their parts of the New World to adopt Christianity, although they were proselytized to.
The Moors are also a large part of why the Iberians were the leaders in the early years of the Age of Colonization--Iberia was one of the most scientifically advanced parts of Europe because of the Moors. Just something for freepers to note.