This is well-put. What I often wish is that there was a different word for these "end of the bell curve" problems; lumping them together with diseases caused b

This is well-put. What I often wish is that there was a different word for these "end of the bell curve" problems; lumping them together with diseases caused by actual pathogens is, I feel, what can cause some of the skepticism about them being "real," because they are clearly not real in the same way that HIV is. Having a clear classification would acknowledge that we know there's a difference, but that we still regard non-infectious disorders as very serious because they can be equally awful in their own ways, and they can sometimes respond to medical treatment.