> But saying "Okay, but we're not responsible for damages" will not fly with regulators, legislators, public opinion or the integrity of their brand.
Why not? It's how everything else works. If you buy a house and then install your own electrical wiring which causes your house to burn down, you have no claim against the construction company and nobody blames them for it because it was your fault, not theirs.
This recent attitude of "people won't understand, therefore corporations have to be paternalistic" is patronizing and factually incorrect. People do actually understand. The worst outcome is that technology-ignorant bureaucrats require companies to clamp down on modding. But having companies do that to begin with is no improvement.
The basis of this seems to be the conceit that manufacturers can actually control their products after they've been sold. It can be true for a time, in the sense that it takes people that long to figure out how to break back into the things they own, but it happens. If you can jailbreak an iPhone then you can jailbreak your car.
Which means that we have a choice. The first option is to accept the inevitable and support it. Expect people to make changes and take responsibility for their own changes, and facilitate that. The second is to try to lock everything down, so that the people making modifications have no access to documentation and have to be running out of date software because the old version with the jailbreak vulnerability is the same old version with the anti-lock brake glitch, which makes it much more likely that people will die. What does that do for your brand?