The idea would be to input certain stamp-keywords that become the only selectable stamps once you toggle that option. For example, I input "tree" and then I can only select stamps that have that tag. You can argue that the group tool and the lock feature serve the same purpose, but I'd argue that you need to type multiple things, select a bunch of things, group etc. When working on a world map that would make my life of drag-selecting certain assets much easier.

First:

It would be useful when I selected an arrea of assets, then with a tool, I could deselect as much as I want, but keep everything else selected

Second:

It would be useful aswell if I could select an area of assets and with the filter, I could select whithin the area I selected, therefore if there are more of those assets on other parts of the map, they would not change