Is it the limitless resolution, and great venue acoustics and sound system?
Is it about the fact you're meeting up with your friends?
Is it about the atmosphere and energy of the crowd? The dancing, the fighting, the mingling?
Is it about the fact that if the performer tells you to make some noise, doing that at home to a video stream would be absurd?
Is it about the fact you might meet an attractive stranger, and go home with them?
Is it the fact you can buy drinks?
Is it about the intrinsic authenticity of a performance by a human, not a recording played by a machine or a copy of a copy of a copy?
Is it about being a singular moment, having experiences that can't be paused or replayed and are all the more real for it?
Is it about getting out of the house, and not being a shut-in?
Is it the cultural cachet and the fact you can post pictures on social media so other people will know you're cool?
Some of these a metaverse concert might be able to provide - you could produce a very high quality video stream with good sound, and an ability to talk with your friends.
Others the metaverse will never provide.