Comment by kubectl_h
I think a well designed winter specific FSD system is probably more safe in snow and ice than a human. For instance downshifting to ensure wheels continue to spin on slippery surfaces, subtle corrective steering to keep the vehicle within its lane, etc. should be easier for a FSD car since it won't panic and over-correct like most people do in those situations.
And if the car reduces speed when appropriate and some assholes start tailgating it, it won't suffer the anxiety of holding up 10 cars that want to drive beyond the safe, reasonable speed for the snowy/icy conditions.
Pretty much all electric cars have single speed transmissions, so there's no downshifting. And modern vehicles have electronic stability control, anti-lock brakes, automatic emergency braking, and several other safety systems. It's pretty hard to overreact with those enabled. The main issue is that people exceed safe speeds for the conditions, making them unable to brake or turn in time to avoid a collision.
Right now, most self-driving software will refuse to activate in conditions of poor visibility. I've had that happen with Tesla's FSD, though in that case it was snowing so much that the road should have been closed. Also when the snow is deep enough that your front bumper becomes a plow, it will refuse to activate.