To be "somebody" may mean to have fame, which is empty. But then it could also mean to have more duties, which can be meaningful but also difficult. Being a somebody like, say, Ah-bien or Bill Clinton involves both, right? That's why they are subject to more criticism.
Being a teacher is being a somebody in a more specific circle. Maybe you also want to be a somebody in a club? Or in your class? I guess nobody wants to be a nobody everywhere; we are all somebody somewhere. That's why, for me, there are different kinds of somebody and nobody.