Great message in this movie!
I think it was about Big Z more than Cody. It was intended to be about Cody but his goals and aspirations aligned with Big Z's legacy.
Its a story about a boy chasing his dream of being like a famous surfer. But its also about a fan mentoring a superstar.
Cody taught Big Z a valuable life lesson which is to stay true to yourself. He said what made Big Z so great was that he wasn't afraid to die. Unfortunately, Z was never tested on that until he lost which led to his decision to fake his own death because of fear of failure. But Cody was a symbol of hope for Big Z to be who always was; fearless, even after the fall.
Just when you thought this was all about a dreamchaser...its also about the complete opposite; running from one's destiny.