[Ntrails]

>everybody who knew him found him to be a genuinely nice and caring person...

Whilst that may be true, I've not read about a lot of tragic deaths where everyone who knew the person thought they were a prick.

The point being raised is "Do we really think his theories had unusual insight/value or is his work being viewed through the lens of his death being tragic?". It seems like an entirely valid question to ask.

In terms of "the joker being a rational actor who achieved his goals". Well personally I think he's misinterpreted the film/characters, but I know i'm not an expert on such things so the most I can say is that I'll take his view with a pretty chunky pinch of salt.