I would say three, if you count StarLink separately from SpaceX.
He has certainly helped maintain Twitter, Tesla, and PayPal at different points, but they were already built before he arrived.
Building a company isn’t about who filed the paperwork, it’s about defining the product, the path to profitability and executing on that vision.
You might not like the guy, but he clearly built Tesla.
That's fine if we want to hold that definition, but then your insistence that Musk built Tesla does not logically follow.
Tesla, the car, was not, but we are clearly talking about companies, not cars.
Is it that you are unaware of the difference between companies and cars?
How big do you think it was exactly when he joined? And at what level of product maturity?
1%. It is at 2% now. Which isn't a knock on what Tesla is doing today, but to tell how it pales in comparison to what the company will be doing 1,000 years from now. We are still in very early days.
If that is how you want to measure it, Tesla hasn't been built yet. It is still under construction. No matter how you slice it, it is impossible for Musk to have built Tesla.