Imagine you're driving in, say, Bergamo, in those very, very narrow places in the Città Alta that are accessible for BEV but not others. Then imagine you're in a Model X. You really, really need very high precision. My oft=posted trip there shows one place that had 8cm on either side. There is zero chance I would have avoided damage were I driving with my vision.
Especially in old cities around the world that is common. Will vision be enough? I do not know. I do worry. That is a common use case in much of the world.
In Southern California and Texas, probably almost never.
As for Model X rear doors, I speculate they'll not eliminate those sensors, visual cues are not very accessible there anyway.
Surely they'll have solutions soon, if not immediately. The new solutions will be cheaper but more mathematically complex. The AI Autopilot team will have fun with these use cases, I'm sure. The visual screen representations will be as they now are, I hope!
As an aside, they must be close to remove outside rearview mirrors. Regulatory issues can be managed. BMW was pitching that in 2016:
The BMW i8 concept car revealed during CES features cameras placed where side view mirrors would be, and on the top inside of the back window.
money.cnn.com
Many others have done this too, and Tesla has repeatedly said it was coming.
When?