If he had been alone, he would have died. Walsh points out that proper clothing is a must for winter hiking. Cotton doesn't retain heat when it gets wet. Synthetic fabrics such as Polarfleece work as well as wool. An outer jacket should consist of both a waterproof and a breathable fabric such as Gore-Tex.
Mittens are much warmer than gloves.
As for footwear, leather hiking boots will accept flexible crampons. But in extreme cold, most plastic double boots accept step-in crampons. Every hike is a calculated risk.