I don't know about that - my Subaru head unit crashes a lot more when I'm clicking around in the Subaru programs, and it very rarely crashes when I'm clicking in CarPlay. My feeling is there are bugs in the Subaru provided programs, and very few bugs in the program that launches CarPlay and gives it control of the screen (probably because that is a very simple program).
So it seems that the more features I use via carplay the less it crashes. It's not perfect, but it certainly helps.