The problem isn’t e.g. CarPlay, it’s the car itself, which is usually entirely custom.
For example with Infiniti they have their own Android based OS and the only way to get a new head unit in the car is to have a full emulator. Otherwise you lose access to anything that the head unit controls.
I don’t know if open source custom car roms will be a thing until we have an LLM that’s smart enough to automate porting the rom to different models of car.
Reduce, reuse, recycle.
They can reuse servers by giving them to me