I have a hunch that as cars get more sophisticated, they also need to have more sophisticated treatment. The reason I leave my car out to have a foot of snow on it is because it works anyway. If the car wouldn't actually
work without the windscreen clear and sensors ice-free, I would either use a garage every night or have a less sophisticated car. And I suspect that once autonomous vehicles get good enough, people will actually want to ride in them - so will keep them indoors more than they do with their normal cars. Effctively then, the rugged cars have become machines we treat like fragile fighter jets.
Still, for a wide range of weather conditions the autonomous car will just say a big NOPE and refuse to drive anywhere. Which is why it must always have manual controls. The autonomous car that could take me to the city through the worse conditions I experience every winter, won't have to take me in it because that car is probably clever enough to do my job as a software developer too.