I struggle with similar feelings, and the idea that depression becomes something that is there but can be put to positive use absolutely tracks with my own experience.
If one cannot get rid of depression then one cannot get rid of heart disease or cancer.
Many people who haven't been stuck in that positive feedback loop have still been blue. Their capacity to feel happiness is muted just like ours, but they are successfully able to get out of that with a behavioral change. That's not always the case with a depressive disorder, and it can take a multi-faceted approach of medications, lifestyle change, sleep hygiene improvement, sometimes electroshock therapy for those people to get out of it.
Pretty sure there are many distinct conditions that we now call "depression".
Your description is very true for some of them, and not at all for others.
Some people might get a single episode, then get through it one way or another, and never have another one.
Others might have a lifelong tendency or vulnerability to it, and in that sense it might always be there in the background. I'm fairly certain I was more or less depressed (although not diagnosed) in my teenage years and early 20's. In my later 20's things were brighter, although I probably had a tendency for some amount of depression, especially during the darker winter months of the year (I live in the north). However, there were definitely times when I wouldn't have considered myself depressed. I'm not sure I'd even say it was "there" at those times, in the sense of being actively present in any way, even in a non-dominant way.
Later on, I got another deeper episode of depression that I'm still battling.
Yet other people might have it always there in some way, as you say.
However used improperly it can end in amphetamine addiction or even psychosis. It's not surprising most mainstream psychiatrists don't like to use them for depression, but it is a powerful tool in the box.
With that said, I also wonder how many of those people had undiagnosed ADHD/if such studies involved screening for ADHD.
Unmanaged ADHD leading to consistent failures in life and other difficulties -> depression/depressive symptoms from the consequences, lack of achievement, etc over the long term, is a pretty common story.
And obviously, the responsiveness of those with ADHD to stimulants is pretty well-known.
Someone I know managed to do that, despite being on intramuscular antipsychotics. Unfortunately no middle ground, the meds keep him anhedonic and abulic, but without them it's mania. I would be careful with stimulants.
Who are you quoting here? What psychiatrists think this? AFAIK, this hasn't been the meta for a long time.
Because fundamentally, I think, it is necessary to try to get people to comply with medication that seems to help sometimes, while avoiding the reality that the way it works is not known.
It may not be the modern psychiatric view, but it’s also true that psychiatrists are just doctors, and many of them are very slow to change from what they were taught in medical school.
Any psychiatrist will tell you that psychiatric medications only treat the symptoms of mood disorders and that they do not know the cause of most of them. It is hogwash that they think mood disorders are "only chemical imbalances in the brain". They know these disorders are polygenic and environmental. But for some people, a short dose of SSRI's or antipsychotics can keep them alive long enough to find out what it is that is giving them so much pain, i mean singnals.