Given the amount of his personal wealth he put into Tesla and the financial tricks he pulled to get further funding (if what is said in Elon Musk by Ashley Vance is true), then it seems likely that Tesla would have gone bankrupt without him. Maybe any rich person could have done it, and electric cars would always eventually be on the trajectory they are now, but he was the rich person that actually did it. He should get some credit for that, I think. But it is right that he didn’t create Tesla, and he should definitely stop implying that he did, I agree with that.
You paid for services rendered. By your logic you should eventually own your neighborhood grocery store because that’s where you buy your bread.