As interfaces have become more flat over the past couple years, the car interface is a distinct hold out that tends to rely on traditional metaphors for visual design. Put simply, there's still a lot of chrome effect going on.
One exception is Tesla, with its clean visual language and contemporary aesthetic.
In these explorations, I pushed some of their designs to extremely basic elements, exploring just how flat one could go. In some cases, the spare UI doesn't work as well. In others, it seems to reduce visual clutter and aid in at-a-glance cognition. As usual, the balance of both is the solution that seems to work best.