Those unnecessary multiple pile ups on snow covered highways can be blamed on drivers. One or more people can take life and limb.
As a general rule, the posted limits can be cut by half, 70 mph to less than 35 mph at reasonable and proper speed for snow and ice covered roads. Less than 15 mph on city streets. A vehicle with automatic brakes must be left in the garage as unsafe to drive on snow and ice.
A little extra time going from point A to point B could very well safe life and limb.