This blogger nails the criticism of Campbell's monomyth in writing. The problem is not Campbell, but that his profound exploration of the human experience has been degraded into a "cookbook" for writing fiction. Critics who don't understand this are too lazy or too myopic to understand the monomyth's power and scope. Criticism is easy; true understanding is not.
Hero’s Journey – Speech Assignment Handouts and Detailed Rubric, CCSS