Media Matrix: Layout Setup

In Organisation Settings there is a section "Media Matrix Layout Setup" from here you can add the default grid size that Media Matrix should use based on a specific area or for the entire organisation

Any child areas will inherit the layout of their parent area, unless they have their own setting. So if you set the layout at the top level / account level it will automatically apply to all other areas unless otherwise specified

Note: Operators can still manually adjust the grid size / layout of the media matrix as needed.