This article on keeping daily notes in one file total vs one file per day presents a powerful use case for editable transcluded notes. The author now uses daily notes as provided by default (one note per day) but created an additional note that transcludes all of his notes so he can view them in one place. Unfortunately, he can’t even run a find command on the transcluded notes without going into Reader mode.
If we could search and edit those sections, and even transclude-link to a new day (or note) and then just start writing in that note, without leaving the parent note context, but then be able to backlink directly to that daily note later on, that could become really powerful.