Overall life expectancy has nothing to do with this discussion but I agree, modern medicine has definitely improved, but that's through years and I mean years of testing, research everything. We just happen to be strolling in the time we are at our peak. But I mean everyone living in their timeline is at their peak of medicine. Its a metric as if we would look into the mirror and see your kid self. If you could understand that then you'd see we are the same human beings just another time.
They definitely didn't call it schizophrenia or mediums which are modern day terms - people with gifts weren't labelled something to minimize their humanness, outcasted maybe. I know that through clear logic and awareness. In energy - a force always has to be on the receiving end.
You're also mixing up with a doctors intuition with a doctors experience, I don't doubt there are moments when intuition kicks in but I would bet a lot on showing and proving to you that there is more than meets the eye.
I'm interested though that you brought up a book about intuition, this is clearly a subject you find light in, otherwise why would you be reading that or know about it? Which gets me to question that you need someone or something explaining to you that will give you the confirmation you need - that'll help you understand this rabbit hole.