…re not stupid people nor are they unable to learn almost anything of interest or value to them. But they are conscious of their chosen ignorance of the vast majority of facts and subjects and skills. They know what they don’t need to know and they don’t waste effort trying to learn it.
…what you want to achieve in that environment. But a handful of things are absolutely indispensable. That is why the most valuable skill for success in diverse circumstances might be the ability to quickly identify what doesn’t matter. Discern what is not of fundamental importance and ignore it.