Many North American tribes still exist today, with a unbroken culture despite the introduced diseases and genocidial intent of invading Europeans. Why did the Aztecs (& Mayans I guess) get completely wiped out after contact with Europeans?
Edit: I am specifically refering to Aztec culture being extinct, not their genetic descendants. I realise that a large portion of present day Mexican & Central American people are descendants from the Mayan & Aztec people.
Quite simple. They didn't. There are still Aztec communities in Mexico today, most easily identifiable by their language, Nahuatl, which is still spoken by almost 2 million people. Aztec cultural traditions still exist, including traditional religion. Yes, that's right, it is still possible to find people in Mexico worshiping Aztec gods. Even the Christian ones still worship in an Aztec manner. And of course there are other cultural signifiers such as dress, art style, etc. The same is true of the Maya, but even more so. Then there are all of the Mexican's who are close dependents of that culture and still practise it, but have become estranged from it due to the Hispanicisation that occurred in the wake of the Mexican Revolution.
Indigenous groups in Mexico, including Aztecs and Maya, are under threat from globalisation and discrimination, especially with respect to their languages and community autonomy. Nevertheless there are some encouraging signs, as indigenous people become more actively involved in educating about their culture, and as the national narrative becomes more willing to accommodate them.