There was a time when saying this on HN would have gotten you downvoted into oblivion. People felt extremely strongly that everything should be possible with cameras.
Even if one believes everything should be possible with cameras, the goal posts are moving. Other automated vehicles use radar or lidar. Even if Tesla achieves fatality levels comparable with human drivers, other vehicles will outperform them. There's not going to be a great market for the most fatal automatic vehicle. It makes more sense to chase state of the art rather than the state of the median human.