Would it make more sense to draw the Broad with the tags ‘belonging’ to each group of people and that there are intersections between the sets of tags? If I understand correctly, with Broad the tags are part of the group, rather than part of the content. Whereas with Narrow, you have the tags directly set on the content. I’m not sure I agree that the total set of tags available in Narrow is smaller than in Broad.

Do you have a picture / thoughts of how this affects the experience when you have lots of content? What’s the difference in the two situations?