I’m not really sure why someone would hire Ive to design a car. I don’t know much about him, but to me he’s mostly known for designing Apple products, not luxury vehicles. Hiring someone because of their name recognition in a role they aren’t suited for would of course backfire. (Again, maybe he does have some prior work that means he’s suited for the job and I’m just unaware)
And a lot of people think he ruined at least some Apple products (too-thin laptops).
From my work experience, you can't give a designer unlimited power because he/she will turn the product into an art project.