Never going to happen. Always-connected cars like Teslas aren’t going to cede control of the entire in-car experience to Apple or Google. That in-car experience will be monetized with things like app stores, advertising, etc. It will be especially important once self driving becomes more of a thing and the people in the car are a captive audience.
Why let someone use Google Maps via CarPlay when they can use the built-in maps which can potentially make a manufacturer huge $ through lucrative location-based ads.
You’ll see other vehicle manufacturers follow as their vehicles become always-connected and their engineers come up with a fully self-engineered in-car system like Tesla and Rivian.