More likely, in two years, everyone who wants a Tesla will have one. Then what? Share price crash.
That's a static analysis. You assume demand (and price) for Tesla is constant, independent of the number on the road, until everybody who (currently) wants one has one.
But the fact is, more Teslas on the road will lead either to more people wanting Teslas or to fewer.
Which it is will depend on whether Teslas are truly good cars.
If they are good cars, more people will want them, and the company on the learning curve will reduce the price, causing still more people to want the car, causing demand to soar. On the other hand, if the cars don't work out, word will get around fast, and demand will crash.
Nutty as he his, Elon lands rockets ass first, so that they can be reused. I'm not so sure I'd bet against him.