The carplay experience is basically the general UX of an iPhone on your car display, which will be better than almost every car manufacturer's UX. That plus being able to have an up-to-date UI for Google Maps with Google's traffic visualization and navigation.
The difference I see with Tesla is that many owners will say that the Tesla UX makes carplay redundant, outside of the iPhone's lockdown on sending/receiving texts and whatnot (although maybe they have an entitlement to use it, certain uses like Google Glass/Focals by North/Cars seem like something Apple would give text message permission to).
I've never used CarPlay but that's the general impression I have of it. Having used Android Auto, it's definitely a huge step up from a regular car infotainment system but not really from Tesla's UI/UX.
Android Auto is also not a deal breaker for me in purchasing a car, not even close, so I'm generally curious why people view it or CarPlay as dealbreakers.
The difference I see with Tesla is that many owners will say that the Tesla UX makes carplay redundant, outside of the iPhone's lockdown on sending/receiving texts and whatnot (although maybe they have an entitlement to use it, certain uses like Google Glass/Focals by North/Cars seem like something Apple would give text message permission to).