This is a foolish move by GM. I'd rather just link my phone to the equivalent of a dumb-screen and let Google or Apple handle my "tech".
I thought so too at first, but wholly shit was I wrong, and now having a car with Google Built-in is a must feature for me from the moment I used it in a Volvo. It's like Android Auto except it works. Always. Without a phone. No disconnecting, no wire or wireless bullshit, no "why the fuck is my phone not showing up in the list" rubbish.
Also Google doesn't "handle the tech", just the backend. It's still largely in control of the car manufacturers except down to individual apps (and having actual real Google Maps, or Waze, or whatever you want to download from an App store is orders of magnitude better than whatever shit car makers used to push in the past).