My newest car is a lousy old 2015 model. I rented a small (2018?) SUV recently and it allowed some of the apps on my phone to take over the screen. I discovered this by accident because my goal was to have the phone connected to the USB for power while I ran the navigation app on it. It was great for navigating to a known destination. It was not so great for finding the nearest Starbucks.
My 2015 piece of junk requires a $500 p.a. subscription to receive traffic data for the navigation system. That is about 5 new Garmins a year, or 1.25 Pixel 3a's, a phone I don't own but have heard good things about.
That's all nice and well, as long as you are in cell tower range. I drove mine cross-country through places where you get 0 cell coverage. Having a navigation system that actually works is pretty nice.
That at the very least presumes that you remember to do that in advance. And that this functionality is actually available to do. Last time I tried, e.g. Google Maps would not download offline maps in some countries.
Still seems like it would be better to just include what's required and then let a phone handle the software.