By ecommerce component, I guess you mean the catalog manager.
I agree that there is a need to have a simple method to somehow enlist all
products that are not assigned to any category and thus a catalog.
As per my current understanding, I think it is possible to achieve this
filtering if you choose the Advanced Search in the Search Products.
Thereafter,
Category: <choose the root category mapped to the catalog>
Include sub-categories? Yes
Select Exclude.
This should enlist all products not associated to any category under the root
category of the catalog you are concerned with. Then there is provision to
perform several mass actions on the results right at the bottom of the screen.
Provision for further search refinement is needed to exclude variant products as
they should not be mapped to any category.
Hope this helps.
