Oregon is a pretty warm climate. Just eye balling the terrain, they look to be at a pretty low elevation and probably won't see more than a few weeks of below freezing weather per year. Not sure this would be practical in a more punishing climate.
A common misconception is that insulation is about heating only. It’s not, it’s about keeping the indoor climate as steady as possible, which means cool in the summer. Even a moderate summer will be balming hot in a tent.