Hi,
I think I understand what you are saying and to some degree I think there could be some truth in these ideas, I have had a couple of psychotic episodes and been diagnosed with schizophrenia, but 'recovered'. My conclusion was that I never had it in the first place, that I was just going through some things in my brain and this was the way it was making me respond (temporarily).
But a couple of psychotic episodes and a misdiagnosis is very different from debilitating life long paranoid schizophrenia which causes a person to completely lose touch with the reality around them and never find their way back to it or be able to function successfully in it.
Schizophrenia is no more a myth than 'furniture' is a myth. Its a symbolic verbal representation of a collection of 'ideas' about a group of loosely connected symptoms and behaviors which we know something about, but not everything.
Furniture is connected via its purpose, and our cultural and social understanding of what we do with it. A chair is still just chunks of a dead tree and 'unusual' behavior is just unusual behavior until we categorize and label it.
Is Schizophrenia a pathway to enlightenment and higher levels of being? Maybe it can be. A lot of native cultures used various methods for inducing trance like and psychotic states in order to achieve expanded awareness and levels of conscious understanding, but it was never meant to be a permanent state of being, if you can't come back and put your new awareness to use in the real world, what's the point?
I agree that in certain circumstances, experiences labeled as psychosis, which often cause 'strange' behavior can actually be transformative in a positive way. But that doesn't prove that Schizoprenia is a myth. Schizoprenia whatever it is, is a horrible condition, it can ruin lives and cause a lot of pain and suffering.
I'm a half full cup kind of person though, and I like the fact that you made a post about the possible positive outcomes which can be achieved via something generally viewed as being nothing but negative.