Business and management work is... not nearly as complex. But the people doing that work have the same highly complex brains as you do. They can handle the same deep complexity as you. So with all this extra mental space, they add layers and layers of complexity to seemingly simple business processes. This complexity builds the moat protecting their turf from others. It creates the irreplaceability that you get for free.
Most of this complexity has no clear business purpose (bureaucracy). Some of this complexity is fiction or invented languages (bullshit). It is all designed to exclude outsiders and prevent anyone not on the inside from being able to tell what is going on or easily get anything done.