Guest permissions to only see groups they have items assigned

Description

Feature request: It would be very useful to have board view permissions. Currently we can set permissions for someone to only be able to view items they are assigned to - it would be great if we can take this a step further and only see groups they have items assigned to the user.

What are you trying to achieve

I have a shareable board with several different guest users. The board has several groups with sensitive information. I want to ensure that the guest user can only see items and groups they are assigned to. Meaning, guest users should see no item details and no group details.