Not to mention, depression takes several forms, and not all of them are related to unhappiness. A common form is related to anxiety, with people experiencing a constant feeling that something awful is about to happen, sometimes getting terrible panic attacks. Given that many of these people live in objectively and subjectively extremely safe environments, much safer than at any other time in history, it's very hard to take seriously any environmental theory of this kind.
Edit: corrected one bad auto-correct typo ("problem", not "purulente") .
People looking for an actual expert discuss these things should watch Robert Sapolsky's talk: https://www.youtube.com/watch?v=NOAgplgTxfc
For example, in the talk, he points out one of the most telltale signs of depression is waking up early, which is completely backwards from the common perception that depression is someone staying in bed all day.
You are playing into the argument, people often don't have a choice to avoid a depression inducing environment, they only have the choice of using drugs or not.
"Instead of removing the conditions that make people depressed modern society gives them antidepressant drugs."
Examining the social factors that contribute to pathology isn't controversial nor does it downplay the role of drugs in reducing harm.
Ooof
Or as the Unabomber said, "Imagine a society that subjects people to conditions that make them terribly unhappy then gives them the drugs to take away their unhappiness. Science fiction? It is already happening to some extent in our own society. Instead of removing the conditions that make people depressed modern society gives them antidepressant drugs. In effect antidepressants are a means of modifying an individual's internal state in such a way as to enable him to tolerate social conditions that he would otherwise find intolerable."
I think you're right. The problem is, this is the only life most of us have lived, and so we cannot imagine it otherwise, like a fish who cannot conceive of a world above water, or even that water is the medium surrounding it. If our entire society is causing this, then what can we do? Wage slavery, oligarchy, attention theft by tech companies, disintegration of community from various causes. Life for so many people is crawling through glass Monday through Friday, then getting shitfaced on the weekend. Is that happiness? How do we escape?