Basic capitalism (and psychology) rules:
Do what is save. Mostly it works. And if not, nobody is blaming you (Quarter-interested Managers!).
If you take a risk you may fail and take the blame.
It is very similar to diffusion of accountability.
It also explains why Tesla is doing it - all of Tesla is an experiment. The car design is a small part compared to the rest and even then the stakeholders are in the game knowing (and maybe because of) it is an experiment.
The typical stock fund manager is not.
True, capitalism rules. I wrote about this principle in my novel Little Robot. The household and service robots that become infected by a virus and behave like zombies are about as easy to resist and destroy as conventional zombies, because unlike science fiction robots, realistic consumer grade robots would be no stronger than necessary to do basic household tasks.
Consequently they're mostly plastic and aluminum, and can be taken out with a baseball bat or a couple bullets to the battery.
Anyways I still think that as the capital cost of founding an automotive startup decreases thanks to 3D printing, we'll see more unique, niche models of automobile emerge that have more distinct personality to them. I hope so anyway.