There should be at least one subject that you understand very deeply. People who don’t get to this point don’t learn what “deep understanding” looks like. They think that “understanding” a subject means having consumed the most popular content on the topic. Once you understand one subject deeply, you can re-apply that experience to learn another subject deeply. If you know one subject deeply, it’s easy to learn other topics to a shallow-medium level — but if you know multiple subjects at a shallow level, you don’t know how to learn one subject deeply. Furthermore, the major edge humans have over AI is the ability to develop a deep understanding of a subject — AI already has a shallow understanding of everything but struggles when it gets to the fine details.