20-year-old me would be terribly impressed by all the things I know today. That’s the magic of time: spend long enough diligently studying something, and you’ll find you’ve made a lot of progress.
Maybe that’s not reassuring to young people hoping to master something big, but I find it so comforting. It’s not about talent, or starting early, or what an aptitude test say about you: it’s about diligence and the magic and time.