"were wearing wool, wood and leather and somehow even managed to do something like mountaineering"
Serious mountaineering is still done with merino wool.
Serious mountaineering is still done with merino wool.
Let's also not forget while down is natural, the material encapsulating it is usually not!
"the only real upside of wool is it is very warm and comfortable to sleep in"
Because that is a big upside to me.
So thanks for confirming my point and congratulations on defeating your strawmen.