I have exchanged multiple (big) PMs with him related to his Ledger wallet, which IMO wouldn't make sense if he was just farming for himself or others (e.g make a question so his alt can answer later).
I thought something was weird when I was answering a user just a few hours ago, his style was familiar, checked his name, and now..... deja vu
The list is a bit longer, not as big as yours but enough to make me think he isn't doing this for farming, I remember reading one of those that it took me quite a while not only to understand his problem but also how to solve his dillemas.
Judging just by the time spent on those private discussions he could have probably grown 10 accounts, in one of them he showed me like 5 models of the equipment he wanted to buy.
I would love to have voted, but I think your poll misses something along the lines of scared, fragile, and mentally unstable. I am not saying that to offend him or make fun of any mental disorders he might or might not have, he just strikes me as the kind of guy who spends an hour deciding what kind of jacket he should wear before he goes out. Calculating the pros and cons of all the jackets he has.
This fits my image of him also, so I'm not going to comment further on what I think the reasons for his posts are.
But I think that all the harm he does is starting endless discussions, and it's not really his objective more like a side effect.