Music-obsessive activity, in general, appears to be about music. You could, on the surface, mistake it for being about music. But in fact what it is about is memory and love.
[Boyhood] focuses on the fact that we should be paying more attention to ourselves, right here, right now. It isn't asking that you be heroic, but it does ask you to be brave enough to live your life, and elevates the everyday to a higher, more melodic plane.