Fundamentally it's a necessary evil. You have to teach the next generation how to act otherwise the society will fail. The only way to make sure everyone is taught the same thing is to apply it via society in the form of curriculum.

The society didn't just happen by accident, and it requires "maintenance" to continue to function and retain that form. It's a fair point that "education" and "indoctrination" are not discrete categories, they blur together.