It's just a weak metaphor that everyone is reacting to. It's hard to believe that one of my liver cells is autonomous, exercises free will and voluntarily does its job. Every cell in the body is essentially born into a caste, given a set task, and operates as a drone doing that task until the day it dies, all under the blanket of a very specific set of hard coded rules. The functioning of the human body on a cellular level does not scream anarchy to me.