I think the way forward for all cars is to have the Android Auto software or Apple car, so what is on your phone is shown on the car's info screen, satnav vendors aren't going to keep up with the application markets.
I agree with this in part.
Personally, I don't get why buyers guides etc. seem to insist on SatNav for future value in a car. Once the car hits 4,5,6+ year old the SatNav is outdated and likely ****. The system in the 4200 will get you home, but I'll more than likely continue to stick my old TomTom to the windscreen instead.
Having cars with Android / iPhone compatibility is a great idea in practice, however, I think the same thing would happen.
4 or 5 years later you'll be hard pushed to find a handset that is compatible with your car, and that you actually want to use.
Make that 10 years and the way Android / iOS go, it'll be near impossible to find one that even works.
Unless of course they make it forwards compatible, but that usually ends in tears..