I am sure there are areas which you know a lot about, which I know nothing about. And conversely for every pair of people in the world. I spend plenty of my ti

I am sure there are areas which you know a lot about, which I know nothing about. And conversely for every pair of people in the world. I spend plenty of my time dealing with my own imposter syndrome, often because there are many people in my own field who know far far more about it than I do. Peter Shor, the OP, for instance. But its fine. You do what enjoy and best at, and find satisfaction in doing it. That is the way to live.