While that is true, it also means that the 'serious firmware' developed for the car probably has stupid problems.
And it might be safer and cheaper to have the option of fixing problems when you find them, because if you don't have that option, you're forced to weigh the costs of a recall against the risks of the issue for every little thing.
Swissair 111 crashed because the operator installed a new entertainment system which overheated.
A lot of serious systems made by serious people still end up with stupid problems.