At the moment the icon:: 🐡 property applies only to each page individually.
This feature request would be for another icon property.
Perhaps icon-hierarchy-aware:: true ?
As an example, you could apply this property to the topmost namespace page.
This means that all of the links to that namespace will use the icon from the topmost page. This would look really neat in the recent list.
Effectively each nested page will inherit that icon without ever having icon:: in their properties at all.
Of course if a nested page did have an icon property, that would override the inherit from the page above.