When I brought it up at a writing workshop, the instructor, a professor and best-selling author, ridiculed me for doing so, saying it was too reductive and has been pretty much deprecated. Apparently it's not welcome in academia. Yet I see it as an age-old instruction for navigating adulthood. People have been writing stories and retelling myths that explore the journey since at least the Epic of Gilgamesh, so I see it as a lesson necessary for the survival of the species.
My simplified version of the journey's message is this: We are born into a state of innocence but as we grow we face challenges that make us aware of both the corruption in the world and our own powers for dealing with it. Our singular duty as adults is to preserve and protect the innocent by fighting the forces of corruption, so that the innocent can themselves grow and face challenges, so the cycle can continue. We need literature and myth to deliver this instruction as the stories show that the hero is always reluctant to hear the call because it requires sacrifice (eg. Luke Skywalker losing a hand) for which the reward is not obvious. It is non-transactional while the rewards of corruption are usually obvious and immediate. The fundamental lesson is this: adult life will not have the comforts and privileges of childhood, but if we reject the call, we may be consigned to a permanent twilight of childhood, where the wonder, honesty and playfulness of innocence are replaced, respectively, by the fear, sham and drudgery of corruption. We became overage infants enslaved to our appetites. In the final stage of the hero's journey, the hero transforms the world into safer place for the innocent. This may not necessarily make the hero rich or happy or comfortable but it gives their life meaning.
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