You're absolutely right—OneNote did have that powerful feature, and many longtime users still miss it. Back in older versions (especially around OneNote 2007–2013), when you marked a checkbox next to any typed or handwritten note, OneNote could aggregate those "To Do Tags" across all notebooks into a centralized "Tag Summary" pane. It was amazing for quickly tracking all your tasks, regardless of which page or notebook they were in. https://www.humantocat.com
You're absolutely right—OneNote did have that powerful feature, and many longtime users still miss it. Back in older versions (especially around OneNote 2007–2013), when you marked a checkbox next to any typed or handwritten note, OneNote could aggregate those "To Do Tags" across all notebooks into a centralized "Tag Summary" pane. It was amazing for quickly tracking all your tasks, regardless of which page or notebook they were in. https://www.humantocat.com