It’s not perfect, but the new (2019+) mazda system is very nice. It’s all controlled by buttons and dials, zero requirement to ever touch a screen. It all feels quite thoughtfully done, especially when you compare it to fords or teslas with a big dumb laggy iPad stuck to the dash.
I choose not to think about it or include it in my mental threat model, the same way I choose to not worry about thermonuclear warheads.
If there’s some exploitable backdoor and Intel gets owned, we’re all boned and there’s nothing we can really do about it. I don’t have anti-ballistic-missile systems, and I also don’t have the capability to make an entire hardware/firmware/os from scratch.
So instead focus on the things you can control and are more likely to happen. Don’t plan for doomsday, plan for every day.