Well there's more story to come so let's wait and see how he turned into this
You're wrong.
1. Ppl who grow up in awful situations grow up to repeat same patterns if behaviours that were mirrored around them, we literally see this in real life all the time. Empathy is learned not innate, and if it's not learned, you get awful people.
2. He didn't throw away Dan's gift bkoz he's soo rich and it means nothing (he didn't throw it away at all). He rejected it bkoz of the emotional implication of Dan buying him a birthday present and was angry that Dan was crossing the emotional boundaries he had set. He literally donates the birthday presents he gets from fans, what??
3. He didn't treat Dan like a worthless peasant. He rightly pointed out Dan's horrid living conditions (bkoz he's literally familiar to it) and literally took him out of it.
Thank you
Hmm IDK trauma comes out in different ways, some people end up like you've described, but it's not all one size fits all. I think the bigger issue is that JK doesn't relate. The way Dan feels about himself vs how JK feels about himself differs. Their thinking is different. When JK life was ass, he was constantly thinking about getting OUT of it. Dan, on the other hand, was focused on getting THROUGH it. I think that's where his issues with Dan lie. I think he finds Dan's attitude very nauseating. Dan is someone he can't understand. Like yes life's beating your ass but STAND UPP 'because that's what I did so why can't you' mentality. (I'm not a JK sympathiser btw he's been absolute dookie trash) I have no explanations for all the crazy things he did other than that man is built on spite, that's what's got him this far, and it's done him more good than harm... until he met Dan, and now it's blowing in his face, rightfully so :)
Honestly this character development doesn't make any sense. A person that had such a childhood and knows what it means to work hard and build a fortune from scratch doesn't treat troubles people like shit.
Jk should have resonated with Dan, since they kinda share a difficult start, instead he treated him like he was a worthless peasant.
If you know what it means to be starving you don't throw away an expensive gift, like it's nothing.
This sob story is only here to try to live people, but on a narrative point of view is complete bullshit..