When I was young I told my friends that if they saw me in 20 years married and not playing music full time to go ahead and punch me in the face. I honestly thought that I would feel exactly the same at 40 that I did at 20.
At that age I probably would have looked at my older self and thought that I had lost my passion, had sold out, become uncool, etc. It didn't occur to me that I would still remember everything that I knew at 20, plus have another 20 years to figure out what actually is important to me and become twice as confident and comfortable with myself.
I felt way more "lost" when I was 20 than I did at 40. I don't think I've necessarily figured it all out. But, as much fun as I had when I was young, I like my life more now.