[macromagnon]

Android has the concept of an Intent[0] which are basically a category of apps that can fulfill a functionality like sending an email, browsing the internet, or dialing a number, etc.

So a developper can create contacts/caller app so that for example, when you click on a call button from say a google search, the OS asks the user to pick one app that was declared to be able to ACTION_CALL.

If I had to guess, I'd say it's something having to do with Teams being given priority on calls followed by failure to having priority for emergency calls and no way to gracefully recover.

Quickly browsing the documentation I see comments like

Note: there will be restrictions on which applications can initiate a call; most applications should use the ACTION_DIAL.

Note: this Intent cannot be used to call emergency numbers. Applications can dial emergency numbers using ACTION_DIAL, however.[1]

[0] https://developer.android.com/guide/components/intents-commo...

[1] https://developer.android.com/reference/android/content/Inte...