This document is normally only available for viewing by those companies aiming to make Google Certified Android devices. Instead, these other systems need to be hidden away under some other heading, such as "Advanced". No notifications. No pop-ups or any other way. More uniformity throughout the Android ecosystem can only be a good thing.
Google have obviously done some form of research and determine that going forwards and given their directions to app developers their gesture navigation system works best.
This is a bad look. You might have to go digging for them in the future. After that date, Google will only approve new devices running the latest Android version, Android 10. And, if an OEM is planning to use its own gestures, they must be hidden under the Android 10 gestures and be accessible via Settings. And to certify a certain terminal you have to present a series of conditions. These similarities continue with pretty much every iOS gesture having an Android counterpart. "The vulnerability is exploitable in Chrome's renderer processes under Android's "isolated_app" SELinux domain, leading to us suspecting Binder as the vulnerable component".
One of the earlier times we featured G Suite was past year when we said it would receive AI for better file organization for Google Drive. That's not the Android I know and love. Google has also been diligent and punctual with security patches, and while these efforts are commendable in their own right, there will always remain scope for exploits and vulnerabilities in an OS like Android. That's music to the ears of many who love custom launchers and still want additional navigation choices. The app then directs you to the Google Play Store entry for Google Maps, to trick you into thinking that was the cause of the "crash".
That being said, a recent vulnerability in Android has been detected. The new policy would effectively negate those customizations.
Even Google's Android 9 Pie gesture system - based on the "pill" icon as shown in the image above - at least was a bit different from Apple's. The company is most likely opting for this move to ensure that OEMs ship new devices with the latest software.