Nested folders on Calendar side dump bar

Would be good to have nested folders on the Calendar side dump bar since it allows tasks to be arranged by Topic/Domain. It would be cleaner than relying on the Tag feature that comes with Notes/Subtasks which becomes disorganised and is arranged out of order (see below on “Test”).

Have attached an example of my Kanban board from Obsidian which could be a way of organising these nested folders. They could be arranged vertically down the dump bar instead of horizontally as shown.