How Shared Workspaces Operate
It’s important to understand how Meetings creates shared workspaces for users. The shared workspaces are stored securely on the Exchange server. In order for a shared meeting workspace to be set up for a user, the user must open the Meetings app and open the meeting workspace. Before the user opens the meeting, the shared workspace is not set up for them, so they will not be able to be able to see tasks that have been assigned to them in Outlook.
However, it is not necessary for all attendees to use the Meetings app in order to still benefit. Even if an attendee doesn’t use the meetings app, action items may still be assigned to them, and they will get an email notifying them about the task, and they can also receive the meeting minutes emailed by one of the other attendees of the meeting.