I mean, that's just not true. You're right that when people buy a Ford, they're not thinking that much about the CEO. But they certainly are thinking about other Fords they've owned, or their friends have owned, or things they've heard about in advertisements or the news. Ford may not be the best car out there, but it's very unlikely to have basic thinks like seals that don't work; and if somehow they do have basic issues, the company will be around to fix it. If you pre-order a Ford, you know there's a near-zero chance that you won't get what you ordered, and an effectively zero percent chance that you don't get your money back.

None of those things are true for a brand new company. Tesla was infamous for having random things wrong with their cars in the early days which the established car companies had figured out a long time ago. And there's a non-negligible chance the company will end up folding before it can give you your product, or before they can fix the product you got.

The amount of money they have, the character of their backers and their CEO, and the quality of their engineers matters significantly.