The author doesn't make the connection explicit, but tools like Figma reduce the need for files as a means of conveying information between parties. Instead, you collaborate directly in the tool, freeing the designer from having to constantly export and send around documents, and freeing engineers from having to chase down exports. Figma also has a feature where you can "shoulder surf" another person as they work. The ability to see what others are doing in the document leads to some interesting interactions. (You see my cursor moving in a way that indicates I'm counting the number of rows in a design; you message me and tell me it's 15.)