I suspect pharma companies and doctors have settled on the term "chemical imbalance" so they have something to tell patients that is simple enough to understand

I suspect pharma companies and doctors have settled on the term "chemical imbalance" so they have something to tell patients that is simple enough to understand but medical-sounding enough to accept. Also, general physicians have to be across such a vast range of ailments and treatment options, they don't have much ability to deeply understand the issues themselves. I'm not one for any great conspiracy behind this. For my own reasons I've researched the topic deeply, and I agree that the term "chemical imbalance" is fairly shaky, but I can accept a fairly innocent explanation for why it's come to be.