Back a few decades ago when there was snow, people were more patient and stayed off the roads for the crews to do their jobs. Today the motoring public demands roads be travelable as soon as possible, requiring more crews to work during and just after a snowfall. Some people honestly believe snow shouldn't ever be on the road, an impossible feat.
In this case, the driver was wrong, no doubt. But it also highlights why plows can't go down the road at 40 or 50 mph, or even at highway speeds, as some people expect. Even at 25 mph, there's enough force to throw snow and slush over bridge overpasses, crashing onto vehicles below.