Itsuki took the typical issue of a JRPG protagonist being the least interesting character in the entire 10 person party and turned it into a legit personality trait many feel about themselves. The game utilized it to tell his tale as one of a guy learning to be proud of how much he pushes his friends to be the stars and protagonists that they are. Itsuki is a character that says it’s ok to not be the star because those who soar need wind beneath their wings in order to do it. Be there for others, and if you’re good at it, then make it your own and get better; turn it into something nobody can do without because it’s so genuine and caring.
Everyone needs support, after all.