And because it's generally acknowledged within anthropological, archaeological and historical fields now that modern research bears out a picture of generally healthy, sustainable populations for most of the foragers of the Americas?
How exactly does this modern research reconstruct the life of American foragers centuries ago, and based on what evidence? Could you cite some of this work? (I'd like to see the original work that presumably explains its methodology rigorously, not popular summaries.)
I also note that you haven't answered Wei Dai's question.
Regarding Malthus and de Vaca, you say:
Malthus *seriously misrepresents Cabeza de Vaca's case -- the Floridians were in a bad way, but they were also right next door to Spanish early conquest -- his accounts of the Coahuiltecs of coastal and inland Texas describe them as a healthy and prosperous people...
Here is a translation of de Vaca's original account:
http://www.pbs.org/weta/thewest/resources/archives/one/cabeza.htm
On closer look, it turns out that de Vaca's description cited by Malthus actually refers to a people from southeastern Texas, not Florida. So while Malthus apparently mixed up the location by accident, his summary is otherwise accurate. Your above claims are therefore completely incorrect -- the description is in fact of a people from Texas, living very far from the boundary of Spanish conquest at the time.
For reference, I quote de Vaca's account at length (all emphasis mine):
Also, regarding this:
Boas actually travelled to the civilizations he wrote about, lived among them, recorded their oral traditions and analyzed their languages, investigated their history and their environmental circumstances. For many people, especially in the Northwest, far North and other relatively late-contacted areas, these events occured within the living memory of their elders.
Earlier you claimed that the native population of the entire American continent was devastated by epidemics immediately after the first European contacts in the late 15th/early 16th century, so that even the accounts of very early European explorers who traveled deep into the continent ahead of European colonization do not present an accurate picture of the native foragers' good life they had lived before that. But now you claim that in the late 19th century, this good life was still within living memory for some of them.
It seems like you're accepting or discounting evidence selectively. I can't believe that all those accounts cited by Malthus refer to societies devastated by epidemics ahead of European contact, but on the other hand, the pre-epidemic good times were still within living memory for the people studied by Boaz centuries later.
From Mike Darwn's Chronopause, an essay titled "Would You Like Another Plate of This?", discussing people's attitudes to life:
Conclusion, graphs, and references in article. As usual, I recommend reading Chronopause.com as Darwin has many good articles; to quickly link a few: