Assigning Action to User Group/List of Users

I am using the Assign Tasks to Business User activity to assign Action Center tasks either to a business user group (e.g., AP Team) or to a list of business users. The activity completes successfully without any exceptions.

However, in both scenarios, the task remains in the Unassigned tab and is visible to all eligible users, instead of being visible only to the specified group members or the specified list of users.

My expectation is that when a task is assigned to a specific group or a list of users, it should not be visible to users outside of that assignment.

Is this the expected behavior of Action Center, or is there an additional configuration required to ensure that tasks assigned to a group or a list of users are visible only to those assigned users and do not appear under Unassigned for everyone else?

Is this a bug ?