I think going through the ice in cold weather is a nightmare scenario. You've lost your transportation and your insulation in one fell swoop. The second that water hits you, the countdown starts.

The clothing you're wearing is also critical. Wool or synthetics keep a bit of insulating power, and stay somewhat flexible. Cotton turns to ice, literally.

Assuming you get out of the vehicle, and out of the water, a waterproofed duffle bag on the outside of the vehicle could be a lifesaver.

I'm not sure I could operate a lighter or a match in the advancing stages of hypothermia. The hands swell and all dexterity is lost. Something like a road flare with a big pull tab may be the only firestarter that will work.

Nasty business all around. Sadly the fellow lost his life.