I'm from an era where jailbreaking and installing whatever you'd like on a device was the wild west, and have seen nasty stuff accidentally sideloaded. Giving people the option to infect their cars with ransomware could get people killed, so not opening that can of worms isn't the worst idea necessarily. That said, FOSS stuff is usually fine, but I highly doubt it would be a fully encompassed ecosystem that you'd be installing. It'll have add-ons, other smaller projects. Tweaks. That's where you'll get into trouble.