From Android's inception, system updates have been delivered from the Settings app, but it looks like that's set to change with Android Q. The folks at 9to5Google uncovered a new string in the Play Store APK that allows system updates to be installed directly from the app, alongside regular app updates.
Google is now testing that particular implementation, with a user on Reddit getting a system update that was delivered via the Play Store. The device in question was on Android Q Beta 2, and while it looks like the update was a minor patch, the phone rebooted automatically and there was a "G symbol with a progress bar below it," just like the ones you get with regular system updates.
The user also noted in a comment that the update was "definitely faster than previous updates," and right now we don't know whether this is a feature that's trying out in the Android Q beta or an early look at broader changes to system updates. We'll have to wait until I/O 2-19 — scheduled to kick off on May 7 — to hear more details about the feature, including whether it will be exclusive to the Pixels or if it'll make its way to other OEMs.
What are your thoughts on getting system updates from the Play Store?