Most cars with FM have at least two or three FM modes with at least 6 presets and one AM mode with six presets. So you get a lot more FM presets than AM. Also agree no-one uses AM in a car anymore LOL.
The UK Government was going to phase out FM completely to be replaced by DAB, but there has been very poor uptake of DAB radios on the consumer home front (not talking about cars here), likely because of dearer price, so FM has been reprieved, until the Government say different. I look on the changeover as similar to years ago when they tried to get Bluray video discs taking over from DVD, a lot of people like me never bought any bluray discs as it was too similar a technology at a dearer price. Still do not have bluray.
My own experience of DAB in cars is lukewarm as some cars have very poor ariel's, especially like my wifes car (a 453 smart Fortwo) which has a hidden DAB ariel under the front wing, looks good for the car being hidden away, but gives poor reception sometimes. Luckly she has a memory stick option, so she can play those stored tracks when radio reception is poor.
There is also another fault with DAB called ghosting, where if you are going from one DAB region to another, you can get a 4 or 5 second repeat of the conversation or music playing, and you go "what was that", or you can get a break in the reception for a second or two during changeover regions.
Anyway you pays your money to buy a car and the type of radio in it. As long as i get good reception which does not fade, I do not care if it is FM or DAB. Mind you some cars no longer give you a CD player,
but that's another story