In other words, this isn’t part of the beta program, and Google is believed to have started the public rollout of the new Assistant Driving Mode to production devices.
The folks over at XDA suggest that this new experience might actually be powered by a server-side switch and not by a specific update for the aforementioned app. This means that you can’t do anything to enable the new Driving Mode, as Google is most likely rolling it out gradually to users across the world.
Once the Driving Mode is live on your device, you should see a new menu in the settings screen of the Assistant that lets you enable and disable this feature and configure other options, such as allowing messages to go through while driving and ignoring incoming calls.
The user interface that this new Google Assistant comes with on Android devices looks a lot like the one of Android Auto for phones. Users are provided with a home screen where they can access essential features, like calls and messages, and apps that make sense when driving, such as Google Maps and YouTube Music. Google Maps is actually an essential part of this new experience, and at this point, it doesn’t look like other navigation apps would be allowed. Not at first, at least.
For now, the release of this feature appears to be happening in waves, but it shouldn’t take too long before it’s enabled on more devices. At the time of writing, it’s still not there on my Samsung Galaxy Note20 Ultra running the latest stable builds of Google Maps and the Google app.