This handy summary of the heroes journey details the characteristics and repeated story arcs throughout history. I believe the theory has modern relevance and the basis for most classic myths and contemporary stories. Additionally his application of his theory is timeless, and adaptable as key elements are added or repeated in a wide spectrum of stories. However, it is important to mention that of course, not all stories fit into this "template" - as this author describes. Although it may not be intended,"…the Hero's Journey emerge[s] naturally even when the writer is unaware of them" Thus I agree, elements of the Hero's Journey may be present, or even completely match someone's narrative. By chance or unintended, this framework is obviously repeated in many great stories.
There are many storytellers that choose to tell an alternative, different, mismatched story structure. For example, in the film "Avengers: Infinity War" - the story at first glance seems to not fit the hero's journey. However, it is formatted as an extended/chopped version of the Heroes Journey: The villain wins at the end of the film - temporarily concluding the chapter. The film in and of itself tells a complete story arc - without losing any "meat" of the hero's journey from a protagonist's perspective - as the villain is the films true protagonist, despite the audience rooting for the Avengers to win. (of course the complete story concludes in the sequel where the heroes ultimately succeed, concluding their arcs)
"The Hero's Journey is infinitely flexible, capable of endless variation without sacrificing any of its magic, and it will outlive us all." Although it may seem constrictive, pretentious or overly analytical to come to this conclusion regarding the theory of the Hero's Journey, I believe the Hero's Journey to not be a magic structure but rather an underlying set of sequences, struggles and elements that are key points to some of history's greatest stories.
A different argument against the hero's journey is that, no all stories are not psychologically structured, or unconsciously based or ingrained to fit the hero's journey but rather, are organically written according to the desires of the writer or the needs of a particular protagonist. Although I believe this to be generally true, I still think the Hero's Journey provides evidence for a repeated pattern in storytelling that proves its timeless relevance, significance and effectiveness in storytelling, whether intentional or unintentional. I believe this quote summarizes my point "… Hero's Journey is universal, occurring in every culture, in every time. It is as infinitely varied as the human race itself and yet its basic form remains constant"
Ultimately, I believe each story has its own dynamic and flavor that is compatible into the hero's journey structure (or fit into one of its individual themes). The timeless (and relatable) theme of self reflection/discovery, growth, challenges, and overcoming obstacles will find its way throughout stories from the past, present and well into the future. It is because these core individual lessons and themes are so fundamental to human psychology and our fundamental nature, and when combined into the hero's journey, they create a definitive, timeless tale.
