We see that right here on Medium with the private-note function for stories. As a Medium publication editor for about the past 6 years, I have always used private notes for what I believed they had been designed for — communicating with writers about their drafts.
I was quite surprised last summer to learn that Medium designers had not anticipated that use, that private notes had in fact not been designed for editors and writers to work on a draft together.
But that's almost a universal practice now, I guess. I use private notes everyday to talk to writers, I've received private notes from editors of other publications about my submissions, and to my knowledge I've never received a private note for any purpose other than editing a draft or an already-published story.
And now I think I've heard that Medium designers are looking to add a little more functionality to the notes, which would be lovely.