The issue isn’t the “Americas”, it is North America, north of the Rio Grande. There was no popular belief in “compelling evidence” until gramscian/postmoderns decided a new “narrative” was needed. The “sources” are junk books like 1491.
Cultures without the wheel, metal working, domesticated draft animals, writing, etc. at no time in history or in any place have supported “large, very complex societies” - not in Australia, not in Africa, and not in N. America.
I for one think history is fascinating, and that we only know a fraction of what we think we know. Your mind seems set on the premise that the natives here pre-1492 were wandering savages barely eeking out an existance, when the evidence is contrary . And somehow, exploring and analyzing that evidence and coming to a conclusion different than the mindset described above makes someone “PC”.
Open your mind friend. There were incredible things going on in the Americas before the white man got there. And admitting that doesn’t make you less of a Republican.