From MS Article (https://learn.microsoft.com/en-us/microsoftteams/meeting-policies-participants-and-guests#automatically-admit-people) it says:
Invited users only | Only invited users and meeting organizers can join the meeting directly without waiting in the lobby. Everyone else, including authenticated users within the organization, guests, users from trusted organizations, and anonymous users must wait in the lobby. On the Teams client meeting options page, it appears as "People I invite". Users added as a part of a distribution group will have to go through the lobby. |
So my question is, how does it know to bypass invited user through the lobby? Do they have to sign-in? If they have to sign-in, do they have to have an Azure account in the tenant if they don't have their own Teams?