Assuming Elon Musk's personality does not clash with Apple's executives (which is a big if as he makes Scott Forstall look tame in comparison), I think the combined companies could benefit significantly from the synergy.
Tesla would obviously get a major financial life line.
More significantly, they get Apple's leading supply chain and operations expertises. Obviously, Apple is not a proven expert in automotive, but there are still a lot more overlaps and I think Apple can hire and scale (as it has in the past for Project Titan).
To key question is, what does Apple gain from having Tesla in its product line?
Since Apple has been relatively tight lipped about Project Titan, I can only speculate. But I think it could play three ways.
- For those that rely heavily on a car (e.g., commuters), car is among the most intimate and important part of their life. With Apple's own car, Apple can exert much greater control over the experience than CarPlay.
- Apple can collect important data for their mapping service, perhaps using these fleet of cars to beef up Apple Maps.
- As self driving technology improves and becomes far more autonomous and safer, it opens up new business opportunities, such as ride service and car rental.
No matter what you think of Elon or Tesla as a company, their cars are amazing. Yes, their cars are not without issues, but they are far ahead of everyone. Apple brings stability, operations, marketing, and design sensibilities, which are all important for Tesla's sustainability as a company.