Vertical and integration like that has been very commonly and often tried in lots of different industries. Sometimes it works out, sometimes it doesn't. In the case of Tesla the work required to make a car and the work required to make a self-driving car are very similar. However, the work required to run a taxi company has very little to do with the labor required for use of the buffs. Thus, for Tesla and most car companies it is best to say I'm going to do what I do best and let someone else deal with that other hard part. It just loses too much focus to try and vertically

Taxis are a tiny niche in the transport market. They're certainly very profitable for the small number of people who run the companies, but they're a tiny niche and they will always be that way. There are too many advantages to owning your own personal automobile when you drive a lot. In turn, people who are driving their own automobile vehicle are the target of all car companies, taxies are an important niche but that is not enough to make a successful car company.