yep, the natives were nearly extinct by the time europe got serious about colonization.
A plague (maybe brought by the first explorers) had cleared most of them out.
Plymouth rock happened in 1620 nearly 100 years after the Americas were discovered, more than enough time for the plague brought by the first explorers to have spread and emptied out the continent.
https://www.news-medical.net/health/History-of-Sexually-Transmitted-Disease.aspx\
In medieval times, syphilis and gonorrhoea were two of the most prevalent STDs in Europe. One theory suggest that syphilis was spread by crew members who picked up the disease on the voyages led by Christopher Columbus. They are thought to have contracted syphilis while in the Americas and to have then spread it on their return when docking at ports in Europe. Sailors are also thought to be responsible for the spread of gonorrhoea from Tahiti to New Zealand during the Cook voyages.
Population in the Americas peaked around 1000-1100 (Medieval optimum), same as the Vikings in Greenland, Europe, and many other places. A multihundred year drought followed, killing 90% of the population in California, Arizona, New Mexico, Nevada, Colorado, and Texas. Probably similar numbers in northern Mexico.
American scholars claimed that the natives had no written language (petroglyphs by the thousands per square mile in many parts of California, Arizona, Nevada, Colorado, and New Mexico- don’t know about Texas). Massive inertia, versus an honest search for the truth, on all sides. The only significant differences with this latest lying historian are that: 1) he is intentionally lying 2) he has zero scholarship to back his lies.