Portal 'Security Groups Access' assigned to a Role (where Users can only see their Role/Security Group) would allow work associated with Specific Security Groups across products (albeit via different Idea Portals per product), and restrict Users from seeing work outside their security group. This ensures groups visibility to their specific role.
Thank you for the request. One potential workaround would be to leverage private portals and only invite specific users for each portal.
At this time, based on current priorities and historical feedback over time, we are unlikely to make specific updates in this area. We hope you can understand.