I'll let you read back over this after a night's sleep.
I get that you're feeling angry and upset and threatened right now. Hopefully a little time and distance will help.
May I suggest you take another read over those links you yourself provided?
Again, you've brought up generic internet argument talking points.
What do you really think though? Having looked into the learned helplessness you've given me a fairly uncomplicated answer. What if I suggest instead that
failed to account for people's varying reactions to situations that can cause learned helplessness
Is exactly the sort of multivariate, multicausal symptom cluster approach that the study of Depression needs. I've advocated here for a view of Depression that treats it as something that can be caused by many different things for many different individuals. I'd argue that many causes can lead to the same place, and that understanding all of these is necessary if we really want to get our heads around what Depression truly is and start to help everybody, rather than just those who fit the favored model of the day.
Beyond that... this reads like copy pasta.
You've brought up class, race, Dunning-Kruger, 'arrogance' (a two edged sword if ever there was one), tried to validate by talking up your achievements (all those As... I've seen enough TV to know that As are a good thing right?). You've "forgotten more cliches than I'll ever know". It's a fallacy! It's ad hominem! (no! it's Superman!) My grammar sucks! I'm a big dummy!
Cool your head a little boy. There are no girls on the internet, nor are their 44 year olds, nor are their BAs (is that the same thing as an Arts degree? That's... kind of weird that you'd want two of those? Maybe I'm misunderstanding what a BA is, I'm not a product of the American system).
There's what you bring to the table. And what you've brought to the table was your first comment. let me put it back here for you and we'll pretend it's someone else's:
No.
You're way out of your depth here.
That to me reads like someone with a prejudice. A preformed opinion that turned out to be based on a misunderstanding of the subject at hand (positivity ratio is not a Seligman concept nor a part of the broader theory. It only comes out of one paper, from one researcher... so the peer review process worked!).
The actual root of Positive Psychology would more accurately be traced back to Aristotle. I won't insult you by explaining the concept of eudaimonia, I'm sure your wealth of education should have given you plenty of access to the concept.
Looking at that comment perhaps you are 44. But you did not come into this with an open mind, you came in with all the brash arrogant rudeness of pubescence and none of the wisdom or caution that might be expected of a grown man.
Go to bed. Rest. Wake up, apologize to yourself and accept that you weren't at your best. Don't beat yourself up or let this get to you, everyone makes mistakes and everyone sometimes fails. I've been just as rude and aggressive and wrong about things in the past, and swallowing that can be very difficult.
Instead of focusing on the fact that I was wrong, I try to focus on how graciously I can admit to it and how rapidly I can accept the new information being given to you. That's a healthier way to frame this such that it isn't as hurtful and doesn't lead me to the sort of self-blaming that can lead into those nasty downward spirals.
I don't know if that way of approaching this blow to the ego will work for you, but it's been of use to me in the past. (There's not a lot of study on 'internet argument and it's effect on Depression'!)