I recently read Fischer Black’s book Exploring General Equilibrium. I’m sure I’d seen the argument before, but one passage that stuck out was the discussion on how something can lose all value when technological advances make it obsolete. It is true that’s partly to blame.

But those companies still send and receive a lot of paper and packages. It’s just that there isn’t any staff dedicated to doing the sending and receiving; instead it’s included in everyone’s job description.