I used to enjoy "The Last Alaskans". The first few seasons they were real sourdoughs who knew what they were doing, Really though, even they didnt live year round off the land. They had summer jobs and homes. The show only showed the fall/winter lifestyle on their trapline. they brought staples, but depended on caribou/moose for meat, and several seasons some of them didnt get a moose and ended up needing to go out for the winter. Very tough to even come close to living off the land. Granted, living above the arctic circle is the harshest environment imaginable in my line of thought. Probably the most limiting factor in the lower 48 is living within game laws.
I love reading of early pioneer/ settlers in Alaska, or most anywhere. I have read quite a few times that a lot more wanna be sourdoughs and just plain old sourdoughs just disappeared over the winter, starving in thier cabin or freezing to a stump. illness, injuries, etc. with little doubt that contrary to Disney line of though, more than a few burials were inside a wolfs scat pile.