The Wikipedia article (I know, I know: terrible source) on Quetzalcoatl mentions that his influence extends beyond the Nahuatl people into Mayan territory and even other mesoamerican cultures, where he is known by different names. I see certain similarities between his representation there and early treatments of Jesus Christ as Christianity spread outward from the Mediterranean, and I'm wondering if there hasn't been a confusion of sources when talking about the two figures historically.

As a broader question: how reliable are discussions of Mesoamerican religion and faith? Have they all been undeniably diluted by European conquest?