gov.ma.covid19.exposurenotifications.v3 nor gov.ma.covid19.exposurenotifications installed. I turned off auto-updates in the Play store (Settings -> Network preferences -> Auto update apps -> Don't auto update apps) and went to sleep. This morning I woke up with a cheerful notification that Google can help with COVID notifications and gov.ma.covid19.exposurenotifications.v3 installed -- the app was pushed overnight over explicit instructions NOT to update (sure, one can say auto-install != auto-update, but it is worrying that forced pushes can happen even with every single relevant UI switch turned off).
adb logcat seems to have the following relevant lines:
06-19 09:27:54.481 1689 1990 I PackageManager: Integrity check passed for file:///data/app/vmdl1074248108.tmp
[..]
06-19 09:27:55.580 1689 5456 D PackageInstallerSession: Ignoring abandon after commit relinquished control
[..]
06-19 09:27:55.649 1689 2530 W BroadcastQueue: Background execution not allowed: receiving Intent { act=android.intent.action.PACKAGE_ADDED dat=package:gov.ma.covid19.exposurenotifications.v3 flg=0x4000010 (has extras) } to com.google.android.packageinstaller/com.android.packageinstaller.PackageInstalledReceiver
(+ lots of other similar intents)
After that the package immediately becomes active: 06-19 09:27:56.539 1689 13571 D ConnectivityService: requestNetwork for uid/pid:10450/30673 NetworkRequest [ TRACK_DEFAULT id=1249, [ Capabilities: INTERNET&NOT_RESTRICTED&TRUSTED Uid: 10450 AdministratorUids: [] RequestorUid: 10450 RequestorPackageName: gov.ma.covid19.exposurenotifications.v3] ]
06-19 09:27:56.540 1689 3625 D ConnectivityService: NetReassign [1249 : null → 102]
[..]
06-19 09:27:56.833 1689 3750 E JobScheduler.Background: App gov.ma.covid19.exposurenotifications.v3 became active but still in NEVER bucket
So no, it is not just "oh those people opted in and just forgot".