Andy, the quote that you posted further above:
"When the first Europeans landed in the Americas, they described it as one vast untouched wilderness. This was about the highest compliment they could pay to the Native people who had lived there for thousands of years." –Bill Mason
I think that this is very much presenting Native American culture as an unrealistic idyllic fantasy, aka the "Noble Savage" trope. Is the suggestion that they COULD have built factories, roads, railways, large scale mechanized agriculture, schools, hospitals, cities, eventually nuclear power plants, who knows what…. but they just nobly chose not to? Sure, the fact is that the colonialists screwed them over so badly that we'll never know how their society might have matured and developed, and what choices they might have made had they developed modern technologies in their own time, following their own philosophies. But setting aside that hypothetical, at that time, the overwhelming reason that the wilderness was untouched was that (a) there were few people, and (b) they HAD no technology.
And you said
"Native Americans did a heck of a job with going way beyond our "Leave No Trace" guidelines over thousands of years, and on a deeper level than following a set of silly rules."
Well, once again, they achieved this by having (perhaps through choice) a tiny population and (not through choice) virtually none of the technology that allows us to sustain the modern quality of life. Reverting to a Native American way of life of that era would be a dramatic shock to most modern humans – a dramatic drop in quality of life – even for the bottom economic quartile of the modern world's population. That's where I think there's unrealistic idealization, you're ignoring most of the aspects of their life and culture that were vastly inferior to modern society (in a material sense, I mean, before a Cultural Relativist excoriates me).
Having said that – yes, I agree that perhaps we can learn from their philosophy of nature. The unrealistic idealization lies in failing to point out that there's a huge tradeoff in implementing those philosophies in the modern world. What it leads to is some very tough choices, major changes and sacrifices in quality of life (at least in the Developed world) and population management everywhere, at least until technology reaches a point where larger populations are sustainable.
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