Agree with part 3. I fail to see why anyone who is willing to pay a premium for a Tesla car would be willing to let random strangers into their (new) car, unless the benefits far outweighs the cost/risks, but in that case, if the other car user has to pay a high price to use a Tesla for his commute, why not just use Uber instead?
This can probably only work when the car is old such that its value has already been depreciated significantly.