Brain content is mostly memory, and I think it has been clear for millennia that each of us has different memories, based on the context of growing up and living a life.

Most people are born equal (excluding people with inherited disorders). When it comes to brain, it’s all equal, but memory is just the electrical impulses going through the neurones in the brain. So memories are not physical things. Meanwhile, the brain is a physical thing that grows in a specific way set in evolution to control the body most effectively.