I don't think a cursor theme is particularly useful as an object. I dont see cursor theme changes being handled by the shell swapping out cursor theme objects, rather I would say when the system is reconfigured the default cursor theme changes.
As far as I can see the main point for selecting alternative cursor themes, is for example a game may install an alternate cursor theme, and refer to it by name, as a more convenient form of uploading custom cursors.
I don't think a cursor theme is particularly useful as an object. I dont see cursor theme changes being handled by the shell swapping out cursor theme objects, rather I would say when the system is reconfigured the default cursor theme changes.
As far as I can see the main point for selecting alternative cursor themes, is for example a game may install an alternate cursor theme, and refer to it by name, as a more convenient form of uploading custom cursors.