Neverwas is a movie about a psychiatrist who has to deal with his own issues and identity when treating a delusional, or is he?, patient played by Ian McKellan.
It also deals with how one person’s delusion can be another person’s fantasy fiction, and how thin the line is between them. Psychiatric conditions may be the last bastion of spirituality and metaphysics in this materialistic world. What is psychic pain? Our spiritual response to relationships? Our response to spiritual realities?
Certainly delusion exists, but many stories portray delusional characters sympathetically so that you want to believe them. Maybe we instinctively believe that there is more to reality than obviously appears. Why did the materialists want to stamp that out? They were probably influenced by demons. Or aliens. Or their previous life as enemies of rightful medieval royals. Or iconoclasts.