How so?

Having used both of them, I'd profoundly disagree with you on that statement. I consider CarPlay a much more elegant solution than Android Auto. Particularly that android auto will change settings on your head unit. The early versions of it also completely disabled your phone screen.

CarPlay is getting way better in iOS 13. E.g. you can finally run different apps on the car screen and the phone! It also has a nice "home screen" with useful widgets instead of just a grid of icons.