but if the teacher is fully shown, or perhaps the upper body (in Japanese culture, people like to see the upper body during webcam sessions, not just the head), then it would still convey authority and confidence while watching the video?
Authority seems to come in part from the actual height difference, so that could be lost if the student watches a video... But standing still gives other benefits, see https://www.genardmethod.com/blog/bid/161977/Sitting-or-Stan...
