I was 11 when I read All Quiet on the Western Front and maybe 13 when I read Innocent Erendira. I don’t remember talking to anyone about these, though I did feel terrible for a few days after. Honestly, no lasting effects.

This is probably the same as the fact that 70% of soldiers experiencing combat stress do not get PTSD and 30% experiencing severe combat stress don’t either. This means human variability is significant.

So it’s a question of whether you want to roll the dice. I think I’ll want to permit the autonomy for my children but it’s entirely possible they’ll be in the susceptible set and be damaged.

Do you have any evidence that there is a susceptible set? Books especially fiction come with two fundamental safety features. Firstly the book never subjects itself upon its reader. The reader is always in absolute control. Secondly the fundamental unreality of the setting allows one to dismiss it.

I recall observing with morbid curiosity a video of someone losing their life to a terrorist many years ago thinking it would be no different than a gory movie. I was very very wrong. It isn't the realism of the simulation that matters its the inability to dismiss what one knows is in fact real.

I have no evidence that there is a susceptible set. That's a "maybe you're right" statement.

I remember clearly as a kid scrubbing my head furiously for weeks after a local spelunking adventure where the guide jokingly told me that, after a stalactite dripped on me repeatedly, that a stalagmite would grow from my head.

As a kid with a lot of anxieties (nuclear holocaust, overpopulation, etc) I really didn't need to be growing stalagmites from my head.

Up to about seven years old, kids take things very literally. Understanding metaphorical speech comes only after that period, and not everyone fully understands even as an adult.