It reflects reality. We've all come so far, some more than others since people like me are older than you'd think. Naruto truly showed the hardships of growing up. We all went through the same things. Crushes, friends, loss of friends, trying to find ourselves and what we want to do with our lives, first deaths, fights with parents and rivals.
It has everything and Naruto and Sasuke are prime examples of kids becoming young adults and the burden of responsibilities and maturity that comes with age and experience.