Unlike the British empire, Spain didn’t really genocide American natives on a large scale. War and conquest obviously did happen, but most natives ended up adopting Spanish language, religion and culture

You made it sound like they adopted Spanish traditions willingly.

There are four known cases of humans independently developing writing systems. One was in Mesopotamia, one in Egypt (historians differ on possible Mesopotamian influence), another in China, and the last was in Mesoamerica. The Mesoamerican writing was totally, intentionally eradicated by the Spaniards and there are no existing derivatives. It's one of the greatest losses of knowledge in the history of human civilization.