I see a few advantages. For my work in particular, I have to rely on creating desk study reports via exporting PDFs from QGIS - this depends on export DPI, page size etc. Following that I have to pull those plans into e.g. Word and it's a messy system.

A python notebook would be a nice way of generating reports of GIS data in an interactive way without being forced to use pages, PDFs, and embedded image files.