Not who you're responding to, but I do drive a Tesla and miss CarPlay for certain things. 1)Group messaging on iMessage 2) audio apps like overcast/mlb 3) Waze/Maps (Tesla's are pretty good, but sometimes it makes weird decisions for me and I like to have a second opinion. 4) Apple Music (At least on my HW3 car, the built in Apple Music app is slow and, in my opinion, poorly laid out). Definitely better than connecting via bluetooth, but I find the CarPlay implementation much better.
I think they could make it an app and people could just use as needed. I definitely wouldn't have it up 24/7, but I'd like the option when I needed. It would also mean I could get rid of the phone mount I have, which is ugly and I dislike. But totally understand why someone would think it's not needed - Tesla is miles and miles ahead of any other car infotainment system I've tried and definitely does some things better than CarPlay.