[Jetrel]

Yeah, this hews pretty close to what I've heard; that the conquistadores acted mostly as a "catalyst to rebellion" for an enormous native population that hated the Aztecs, but felt powerless to overthrow them.

When these strange foreigners showed up and offered an alliance, their mysterious/inscrutable prowess (technology, foreign backing of unknown power, clear ability to ship in men and arms) helped give the rebels the confidence to give it a go.