I don't think that historians discuss American Nations. The author, Colin Woodward, is a journalist rather than a historian. The book actually falls within the discipline of Geography rather than History although there is obvious overlap.

American Nations assumes the Doctrine of First Effective Settlement, "Whenever an empty territory undergoes settlement, or an earlier population is dislodged by invaders, the specific characteristics of the first group able to effect a viable self-perpetuating society are of crucial significance for the later social and cultural geography of the area, no matter how tiny the initial band of settlers may have been. (The Cultural Geography of the United States by Wilber Zelinsky 1992).

I would suggest a different book, Albion's Seed by David Hackett Fischer, which is very similar to American Nations but is carefully written and documented by a historian. Historians praise Albian's Seed." It analyzes these British colonial cultures: the Puritans, the cavaliers in Virginia, the Quakers and the "Scotch-Irish" from the North England borderlands.

Another book was written to rebut the Doctrine of First Effective Settlement. The Big Sort: Why the Clustering of Like-Minded America is Tearing Us Apart by Bill Bishop suggests that modern day mobility and self-sorting has negated somewhat the effect of the culture of the settlors.

Zelinski followed that with Not Yet a Placeless Land: Tracking an Evolving American Geography.

I asked on r/geography for comments about American Nations and the Doctrine of First Effective Settlement but got no answer there. Sorry I can't answer your question any better. I do recommend you take a look at Albion's Seed.