>>It's intuitive, that a general should not know about the flawed boot of a soldier.
Yes the army is a good example, with the caveat that if too many soldiers have flawed boots, i.e., there is a problem in the supply chain that results in many flawed boots, and this results in many soldiers who appear ready but are actually not ready for battle, the general better damn well know about this flaw.
As the saying goes: 'privates think about techniques, sergeants think about tactics, lieutenants think about strategy, and generals think about logistics'.
So the article is right that the key is to be able to run up and down the chain of abstraction as necessary, usually filtering out the details, but raising prominence of key details that will affect system performance or that can cause unexpected failures.