Microsoft has announced that they will soon be adding a notification that an incoming call is likely to be spam on the call toast notification.
On the Microsoft 365 roadmap the company writes:
The spam call notification feature automatically evaluates incoming calls and identifies probable spam calls as “spam likely” in the call toast. Users still have the option to answer or reject the call, and all “spam likely” calls (regardless of whether they were answered or rejected) will also be reflected in the call history list.
Support for the notification will be coming to the Windows 10 Microsoft Teams client and on the web, and will be rolling out in late August.
If desired, admins can disable it by using the Set-CsTeamsCallingPolicy -Identity Global -SpamFilteringEnabledType “Disabled” Powershell command. Microsoft of course does not recommend this.