I work for a large size corporation but one which is a quarter the size of many fortune 100s. I guarantee you almost no one knows how things work or are done beyond their immediate scope. Much of my life is spent just trying to glean an understanding of some adjacent function or trying to convince people above me that things they believe about how things work are not actually reflective of how they actually work.
A Rube Goldberg machine usually accomplishes one task. Corporations at scale don’t resemble them mostly because, as there are a multitude of concurrent tasks in flight, the Rube Goldberg machines are neither complex nor absurd enough.
I think the primary difference is that for Musk, his companies are actual means to a non-monetary end (electrification of transport, Mars colonization). This creates a tremendous levels of focus. Most companies exist to make money for their owners, and any actual useful work done is only a side effect.
Everything? No way, that's not humanly possible. But he does know a lot and more importantly is a fantastic engineer and can understand any part he needs to.
The majority of companies are run by people who would have trouble understanding the details of what their company does.
A Rube Goldberg machine usually accomplishes one task. Corporations at scale don’t resemble them mostly because, as there are a multitude of concurrent tasks in flight, the Rube Goldberg machines are neither complex nor absurd enough.