When we think of character, we normally think of enduring qualities of virtue. Noble traits like compassion, integrity, and courage come to mind, as do leadership qualities like loyalty, optimism, and curiosity. Common wisdom convinces us that cultivating a strong character is a pathway to a meaningful and productive life. So, the idea of character plays a central role in how we evaluate leaders and ourselves.
You are absolutely correct. Our notion that a some unspecified age we just are who we are with no way to change is one of the greatest lies we tell ourselves. There is no reason you cannot learn new and beneficial habits and behaviors throughout your life. You can even become smarter.
I use this Skills Framework to help me determine how much effort I will need to put into making gains: Intrapersonal, Interpersonal, Leadership, and Business. Moving left to right in this list will determine the level of difficulty in making changes (intrapersonal being the hardest, business skills being the easiest). This makes sense given intrapersonal skills are developed earliest in life and leadership and business skills are developed later. Like the saying goes, "Old habits die hard." But it is possible to change. Through daily insight, reflection, and deliberate practice, we can begin close the gap between the leader we want to be (identity) and the leader that we actually are (reputation). Nobody said it was going to be easy. There is no magic sauce when it comes to being the best.