I am worried that this is a long question and not an answer. What does it mean to become a person? Or we are also individuals. When we say that we are individual, we think that we have a personal idea of what it means. They seem to be, but they are not. If so, if we do not see individuals, we rarely derive individualism. We think that we are more personal than ants, but they may classify ourselves as more personal than us.
What is a carpool? An effective ride where at least two people go to the same place in the same car. What does this mean? Instead of individuals bringing lots of cars to work or school, they can all get in the car and go to the same place together. Is this a better choice? These people are friends, colleagues, and families. In other words, these people will meet each other by car. This has proved to be a better choice for everyone who drives alone from one place to another. Let's face the reality, driving alone alone often becomes dull. As an added bonus, these carpools waste less gasoline and contribute to the environment.
Individualism does not mean selfishness. This means expecting personal choice and decision. Groupism does not mean intimacy. This means that people know "whereabouts of people" in life, which is determined by society. From the physics point of view, people in the individualist society are like atoms flying in the gas, people in the collectivist society are like atoms fixed in the crystal. This dimension is thought to be able to go back to the emergence of agriculture and its large scale society. Until then, I will personally understand team members and leaders. This is impossible if thousands of people have to adjust their lives. Strong entities will not accept leadership, today's society can not succeed