Do these laws mean anyone can go and manufacture parts in any way they want? If yes then they the pendulum just swung too far back. Defective parts should be removed from the market before accidents happen - not after.
(Moreover firmware is not exactly like any other part. Defective firmware tends to be much more common than defective screws)
> and allow third parties to interface with them
"interface with" does not sound like "reprogram". Or did your laws include that too?
> "Open Source Cars"
I really meant "not locked down cars" here, sorry for the confusion. Open-source and lock down are quite different things, unlike what the GPLv3 activists want us to believe (with apparently some success on my subconscious already... damn)
> ... have been on the road forever, so if you are afraid of them stay away from the roads.
I am doing my best already. Letting practically anyone go and drive something as dangerous as a vehicle on an open road is a crazy idea which has killed, harmed and disabled millions of people already in practically every family - and still counting. Car modding is just a thin, new layer of icing on the road death cake. Just a few extra, statistically insignificant casualties.