I think it is a double edged sword. Could be good for some and for others not so good. Sometimes a persons personality can get in the way of the music they create, and sometimes the music a person write can get in the way of who they are. I think the music should stand alone and not interfere with the persons personality or vise versa. I write things that are sometimes miles from who I am. Is Al Pacino really a gangster/Godfather?
Nevertheless, some people have great personalities and are not shy, and I see no reason why they shouldn’t be allowed to show it off. But in the end, I really don’t see the connection between the music and the personality.