Thats in part because theres no good way to know which antidepressant or type of therapy could help a given patient. Medications are prescribed through a trial-and-error method, so it can take months or years to land on a drug that works if it ever happens. And spending so long trying treatment after treatment, only to experience no relief, can worsen depression symptoms.
Their ignorance over what drugs to give was overshadowed by their desire to get as many people on them as possible. Their practice of using the 'throw it at the wall and see what sticks' method is responsible for making things worse in MANY people, but they did not care as the profits were very good and no one was ever able to do anything about it. I am glad this research as been done so that maybe...
maybe... they will at least try to give us the correct medication before bleeding their patients dry from their excessive gouging over trying dozens of medications in a childish attempt to get one or more that will work enough to put you on a permanent cash drain over having to take them. Because, once you start, it is hard to get off of them. The damage they could do can be permanent. But, good luck trying to explain this to a doctor who is driven to make money from convincing you to take them.
Healthcare is the number one profit generator in the world.
Healthcare should not be about profit.
(Yes, I am aware that medication helps some who use it. I am very glad it does. However, the medical profession's desire to toss pills at mental health issues without any attempt at actual treatment (therapy that lasts longer than fifteen minutes a session and more than once a month) is dangerous and shows a lack of willingness to actually manage the issues other than creating zombies who will go out and be good little wage slaves without bothering anyone.)