I can see the point in theory, but when this would've been really helpful, my experience is 80% of the time the video maker's hand is obscuring the important stuff, and the video is often out of focus or frame anyway, and a red circle on a photo as an alternative will usually do just fine. The nice thing about still photos is, the photographer REALLY has to think about each shot, and if it is showing the important thing they want to reveal in that shot. If it isn't, they're forced to either retake it or take extra photos to get the point across.

With a video, the videographer is distracted by talking and doing a thing at the same time, and they just think "Yeah, it's video. I got it." and they often don't even rewatch the footage.