I think the person you are replying to is saying that the entire flow is a single action: you hit screen shot, and the screen shot is taken, edited, and shared

I think the person you are replying to is saying that the entire flow is a single action: you hit screen shot, and the screen shot is taken, edited, and shared to some configured entity, in one step. Seems pretty obvious to me why a single step that doesn’t remove you from app flow would be waaaayyy more useful than needing to use any other apps to complete the job.