>>380820926
There's a couple of main reasons. First is the FOV is between 90 and 100 degrees for most headsets. All you have is voice and vision, you have no sense of touch or any of the other cues that tell you someone is nearby. People sit in circles and talk to each other like normal, but but if there's a mirror some people prefer to sit in rows and talk "across" the mirror.

Second reason, especially my case, I am much more aware of my body language with a mirror and it helps just like the mirror in a in a dance studio. My avatar isn't exactly the same proportions as me and the IK doesn't exactly follow my pose because it's estimating the in-between points. A mirror helps keep you in position.

Third reason is tons of people in this game are some degree of narcissist and want to fuck their own avatars, so the more they see of it the better.