Ignoring the poll question, but addressing the topic that prompted the question...
Car manufacturers dropped AM because it was clearly interfered with by the vehicle electronics and they didn't want customers complaining about it.
Do note that though FM is more resistant to it, FM reception *is* degraded by the noise (just not as much) but it's not as *obvious* to the listener; they just chalk it up to weak reception. Same thing happened w/ the DTV transition; w/ analog, it was clear when a neighbor was interfering with you; with DTV people know their reception is flaky, but they have no idea why, and just chalk it up to weak signal.
As a ham radio operator, one part of me would like to see broadcast AM mandated, because holding vehicle manufacturers to a higher standard of interference suppression would be good for the RF ecosystem overall -- just just on my sensitive ham bands, but for cell phones and everything else.
However, I'm against useless legislation, and my fear is that saying "You must put an AM broadcast receiver in your car" isn't going to achieve anything useful. Now that they're only putting it in because the law demands it -- not because most of their customers are listening to it -- if the law doesn't say they have to put a *good*, *useful* receiver in there, then if reception is trash due to the local RFI they just shrug and say "Well, that's why we didn't want to put it in!" and nothing was accomplished.