A better person, I don't know. A different person, that may be. A person that opened his eyes on some things, surely.
Well, first you need to enter an alternate state of consciousness out of dancing to the power of music. That's kinda hard and you can't control it. That's something that happened to me a few times spontaneouly because the music and the weather, and the ambiance were all perfect. Else, it's easier to do so with some psychotropic help, but we aren't talking about that, are we?
Well, so, everytime I came back to Earth after such an experience, I had the feeling I needed to relativize some things in my life. Like, think about what's really important in life, what to change with daily relationships, etc.
Maybe your frends didn't go as far as you in the trance-dance thing, maybe they're listening to styles of music that are less prone to slingshot them over the coulds, but overall, I tend to agree with you with a nuance: based on my own experience, I'd say you won't be changed or made better in a finger snap, but you'll start reflecting on your own life...which may induce some changes. In other words, the transient state helps opening your mind to oneself's changes, and whether changes happen or not, takes place after, and is entirely up to you.
With some drugs, in some conditions, though, it goes much further, and you can definitely get "altered" dutring a psychedelic experience, not always the good way, unfortunately. I wouldn't advise doing so.