I don't disagree, and most of what I know about Tesla early history comes from the Isaacson biography, but: it seems pretty clear the "actual" founders would never have been able to clear the hurdle of scale production without him. It wasn't just the funding (which would have been hard to come by), it's really hard to build a large, real-things-in-the-world industrial company from scratch, doubly so for something as complex as a car with all the complexities supply chains, regulations, literal factory construction require.
All glory to the guys who started the company (I love my Tesla Y), but I don't believe it would have gone anywhere without Musk.
(I was add something about Stacy Munro and the auto industry, but I'll just link to his first teardown of the Model 3[1].)
[1] https://www.youtube.com/watch?v=CpCrkO1x-Qo