There doesn't seem to be any point to this discussion for GP to miss because the premise was plainly incorrect. As multiple people have pointed out, Android itself is completely independent from proprietary services. If you buy a Google-flavored Android device (which is a spectrum itself), your device will come with proprietary services on it. That doesn't mean you have to use them, nor does it mean you have to have a Google-flavored Android build. You're free to use apps that use Pushy or some other third party push messaging service, OpenStreetMap or some other map provider, Bing or some other search provider, Fastmail or some other mail provider, etc.