Medicine is super-bad about not being able to tell a symptom from a disease. A lot of "diseases" are just symptoms with Latin names and a set of empirical remedies.
Psychology in particular seems to have come to the conclusion that if you can name an assortment of 4 out of 10 symptoms, that counts as having identified single disease.
I think part of the problem is that we're so good at applying various techniques that no one bothers to think anymore.
Well historically the symptom /was/ the disease effectively without imaging to meaningfully separate "appeasing the spirits by ritual boiling" vs "killing microbes". To go with a niche mixed metaphor part of the issue is epistemological low resolution. If the extended "senses" and knowledge are lacking everything is imprecise.
One path of medicine closest to that sort of symptom vs disease separation being practical is phage therapy. It could be called true alternative medicine as an actual alternative as opposed to a euphemism for "false or unproven" but is generally less practical in spite of its other virtues. Because a proper phage needs to be selected per target pathogen. As opposed to not caring what strain of virus it is and just treating the symptoms so the patient can recover and not die.
'Medicine' being a stand-in for 'diagnosis'? Because medical research is all about underlying causes these days. Maybe 50 years ago it was just a corpus of traditional cures. But those days are gone.
Psychology in particular seems to have come to the conclusion that if you can name an assortment of 4 out of 10 symptoms, that counts as having identified single disease.
I think part of the problem is that we're so good at applying various techniques that no one bothers to think anymore.