Don't you think Mozilla's message would be much stronger if their privacy guide had an example of what the legal agreement should look like? I didn't see anything like this, maybe I missed it. Clearly manufacturers have gone overboard in some cases, but I don't believe it's that easy to make you guys happy.
There are lawyers in the audience here, how about post some legal contract that protects manufacturers from a passenger pressing the OnStar button while the driver is in the gas station bathroom and being liable for anything resulting from that, and every other possible liability from OnStar. I'll take my -4 and your lack of constructive counterargument as the answer I know it is.
If contrarians really wanted to be helpful, they'd not downplay risks inherent in the utter lack of basic privacy legislation in the US and pretend this is all fine and normal. But instead they shill for car manufacturers, pretend adtech is harmless and try to portray anyone who has a problem with these things as weirdos.
If Mozilla really wanted to be helpful they could suggest legal terms to cover the manufacturer for features people want, such as crash reporting or locating stolen vehicles - except I suspect that Mozilla would feel obligated to issue a scathing review of Mozilla's suggested privacy policy were they to do so.