Easy: separate the systems into the safety-critical ones required for driving, and the nice-to-have ones used for things like entertainment. You can now give the car's owner full access to the latter via all sorts of weird 3rd-party apps, as there's no way for that access to cause serious issues.

They should be doing this anyways, or else you end up with your Jeep being crashed via wifi [0], and having the blast radius of a corrupt album image [1] restricted to infotainment is probably a really good idea too.

[0]: https://www.kaspersky.com/blog/blackhat-jeep-cherokee-hack-e...

[1]: https://www.theregister.com/software/2022/02/10/radio-statio...