The civilization found at the Inca structures was most probably descended from barbarians who conquered the civilization that built them. It's like someone arriving in Europe, finding the Franks ruling over it, and assuming they built the Roman Empire.
> Bonanza of new dates rewrites the history of the Inca
> The traditional Inca chronology has collapsed
this is clickbait, better title:
Archaeologists find evidence of Inca expansion 50–100 years earlier than previous estimates.