If you have an android device with Google services and a firewall, you'll see that the device is constantly phoning home, which is also noted in the privacy policy.
This does nothing for privacy, rather than provide the illusion of privacy.
I'm mistrustful of Google's privacy stance, since they have a history of changing their privacy policy, then misleading users about it. Remember when they implemented personally-identifiable web tracking and sold it to users as "new features for your Google account"? Merging Doubleclick's tracking data with my Google account doesn't seem like a feature to me.
[0]: https://venturebeat.com/2017/04/06/following-apple-google-te...
[1]: https://www.propublica.org/article/google-has-quietly-droppe...