I completely disagree. These things need to be extremely simple and clean and most of all consistent across devices and car models. When driving, the last thing you should be doing is fumbling around looking at a screen. By making is so simple and forcing all manufacturers to adopt the same deisgn it means whatever car I get into that has CarPlay, I get the same experience and can focus on driving rather than searching on a screen. Imagine renting a car and being told it has CarPlay which you may have in your car and then you go to use it and it looks completely different. That would suck and push people away from using it IMO.
It doesn't look nice
Are you suggesting that BMW Audi rehaul their interface to look like iOS 7?