I think it's common for people to dwell on trauma memories, either that or they avoid thinking about it (if they can control that).
Idk about the link between childhood trauma and being obsessed with things that remind you of childhood. But I know geek culture involves a lot of heavy fixation on videogames, films, animations etc that most people are introduced to in childhood, but the geeks never outgrow it, they stay immersed in that culture. I read somewhere that this could be a form of fantasy exploration / escapism for them, especially if their reality falls far short of what they wanted, they can meet their needs that way (also may explain the appeal of rpg or cosplaying perhaps, though I think cosplaying might be more for artistic types who are an interest in costume design / makeup etc, or they enjoy the attention of dressing up and having photo ops with other people). 2. They tend to love elaborate stories as well I've noticed, because a lot of geek films will have loads of sequels / prequels. They're also usually obsessed with sci fi, but then again, when sci fi is done well it's pretty philosophical and I think intelligent types would be drawn to this. I don't get the impression most geeks are traumatised by their childhood but they are definitely obsessed with it.