My ex-husband, the cardio-thoracic surgeon, and I used to have a routine. He LOVED watching survival shows like Naked & Afraid, Dual Survivor, and anything with Bear Grylls. We used to watch these shows on our very rare off moments we'd have to share together. I personally am not a survivalist type of person. If the world collapsed today and there was no Walmart to get groceries from, I'm completely useless. John, however, came from a very poor family in the southern US. He's what you'd call a country boy through and through--Blue collar background with a white collar education/profession. He grew up with alcoholic parents that pretty much ignored their dozen kids. The kids certainly had to fend for themselves so they all know how to grow crops, hunt, fish, camp, and otherwise live off grid. I used to love that about him actually.
So getting to the point, in all of these survival shows, they mostly go about showing survival in tropical/subtropical climates because no TV station wants to stick two people out in Siberia naked and risk that lawsuit. It's much more predictable to stick naked people in hot climates and tell them to survive for 28 days on inhospitable islands or alligator-infested swampland. Exposure in these climates would be less detrimental than if they were dropped off in Siberia.
Only a few survivalists actually go into colder climates like that of Croatia or Canada... the thing is when I've watched these survival tests in freezing tundras, almost all of them have said the same thing:
The worst thing you can do in a survival situation in below freezing temperatures is to break a sweat.
To be honest, I'm a little surprised nobody has brought this up before. I've never been comfortable with the den because if they actually built that den, they'd have certainly broken a sweat doing so turning their already poor odds to lethal. But they'd HAVE to have known that!
So I don't get it.
In a hypothermia theory the breaking into a sweat would begin on the ridge, when digging a 12x4ft trench, 3ft deep, in a crusty snowcap following an arduous ascent, and logically explains why the trench diggers were stripped down, which would be to air themselves off, their backs wet.
The critical mistake is then to sit in an unheated tent, possibly doing so because either the wind was suddenly too strong to support the elongated tent ridge, so the overhead stove couldn't be set up, or they didn't bring enough fuel and had to put off lighting it until bedtime. If they had limited wood with them, taking only a small amount because they had originally planned to crest the ridge when they set off, they couldn't risk burning all that fuel before the coldest point, around 4am, to which time someone would need to be on fire watch, to reload the grate every few hours.
Rather than first becoming hypothermic and then paradoxically undressing, the hikers would have stripped down when they were warm and sweated from their exertions, and then their core temperatures gradually fell in an unheated tent until they felt warm through hypothermia's effects and then remained paradoxically undressed
, convincing themselves things were not that bad and they were tough enough, so they didn't redress themselves and recover the situation. It's possible they may have had to fell the tent as the wind picked up too, perhaps cutting through and then kicking the ski pole if the support rope was tied too tight and frozen, so then things get far worse when they are in an icy grave, in their trench.
An experiment was conducted with 9 people walking down the pass at night, and they all arrived at the forest unscathed and so assumed the 1959 hikers would have managed that without issue, but they had modern fabrics, footwear, gloves, hats, coats, and were not chillled and exhausted to start with. It was an entirely meaningless experiment, because as you suggest, potential compensation claims would be made if a realistic experiment was done, where they may have fallen and gashed/scarred themselves on the numerous rocky ridges, or developed frostbite. Even if a medivac had stood by who would want to risk that.