> I'd be really concerned about failure modes here.
I'm so happy failure is being addressed. Because to me (as a former engineer) this is one of the most important factors. In addition to failure due to snow, what about it just breaking? A small rock or crack is not going to greatly obscure a mirror's view. More annoying, but you can still get most information. A smaller lens does have the advantage of a smaller target area but more potential for complete failure. It is also more complex and with more complexity there are more modes of failure.
For example: I used to drive an old truck. The mirror adjustments just did not work, but I could manually move them. Dead simple and the purpose of the device is still achieved even when something broke in the device's chain. With a camera you have the screen (which can seriously affect your night vision! I'm EXTREMELY annoyed about this in my current car), every point of connection from screen to camera (software and hardware), the camera, and the lens. I'm under the impression that not much can go wrong here in the product chain and you still have a functioning device.
BUT the camera does have clear advantages! You can use IR so you can see at night. No glare. Better angles. Software that can do object detection and help you avoid accidents. It is a matter of trade off. Typically in machines that can easily lead to fatality we tend to me more risk adverse.