When we introduce ourselves at a meeting, we all take in so much information with our eyes. What you are wearing, whether you have glasses on, what color your hair is, whether you are attractive, etc. Visually impaired people get no such info from someone just stating their name. So descriptions just sort of help level the playing field.
This is all new to me, so I suppose you could google just like I did.
Here is something I just read
For a visually impaired person who has some level of sight, having descriptions of physical characteristics can help them recall individuals and identify them on a second meeting.