That may change as we read less and less as a society. Most of my generation 80's kids did have at least one book or story that inspired or influenced us. However kids read less and have a lot more competing for their time in terms of social media and internet access, so the impact of a special book or character hopefully won't cease, but it will likely be less prevalent.
If not a book, because they are not huge readers, they have a favorite movie or musical artists that influences them. We idolize these people and they help us to form our world view. I can definitely think of a few books and movies that have influenced me and my goals.
Every person has someone that they looked up to as a child. Many people look up to athletes. Some people look up to politicians. These people have a profound impact on what a person might decide to do. The influence can inspire and encourage, as well as teach the children about what they might do as adults.
The right book, it’s said, can change your life. Some books can alter perceptions of the world, or let a reader see life from a perspective they may never have considered before. Others expand the sense of what’s possible within the confines of a narrative; still others tell stories that the reader might not have ever expected to find themselves hearing.