I think it's all depends....like if its 'sad' all the time and they explore then its good, but if its prisoners or problem childs to be forced to have tests then take meds then that's where it is questionable....
it doesnt go down to the real underlying problems, SOCIAL problems, at home, school or what not....it a case of chemical imbalances.....my (additional) point being is sometimes I must wonder of the 'imbalance' is not inherent or biological flaw but as a reaction of prolonged situation of the undesired or unacceptable or even slightly hazardous, like a hard unfeeling parents or such wise...it could trigger life longer dissapoint which creates subdued moods which became habitual to hence a 'depression' but a kind that get misdiagnosed, not just a medically misdiagnosis, but of the social nature......the people! the circumstances!!....so yea counseling, or a chance for change of circumstance could do a lot, like, leaving town to a different place start afresh....problems is two other difficulty, many people CAN'T LEAVE!! ( & don't blame them) other is when arriving onto new place(s) their habits has been became mildly destructive (not violent) but in terms of not being able to create new social contacts (or re-create)......people have loss of power...oh another factor is, the new places/people could actually contribute to worsening or re-trigger the blues because they don't understand or are quite defensive (don't blame them too).....its a really icky business.....
but, as a tool for diagnosing, this is welcome and yes many people are and can well be unaware and it would create a lot of potentially life-saving changes but then they have to work at it too......
its just what concerns me a little is if govt starts to roll out 'intervention programme' of a rather significant quite scale say, to test more than 50% of students in schools......then that's when my eye brows would be raised...as it would be in my eyes, state-control, a la 'big brother is watching you' mindset....that would be deemed as abuse of technology and medicine...