Sorry, I don't have your extensive knowledge of parenting so what exactly do you mean by "addressed by"?
Imo kids have plenty to be doing and thinking about while growing up without having to get it into their heads that horrible things happen to people in both fictional and real situations.
Having sneaked up to watch a lot of movies I was too young to see, when I was a kid, I can tell you now I saw a lot of things I'd rather not have seen at that age. Kids should be playing and laughing like kids, not learning why Jimmy is having his head stoved in and car burned by Franky Knuckles.
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For instance, do you think you need to expose a 6-yr old kid to the horrors of House of 1,000 Corpses or the remake of Texas Chainsaw Massacre, just in case they get attacked by a family of weirdoes while on a road-trip in some 10 years time? Just the fact that they wouldn't make any sense of the plot or motivations makes that funny; the actual content of the films makes it a sick idea.
I think you'd draw the line before those particular films (if not, I pity your future kids). But now we're at a point where we have to ask "where should a line be drawn?", which we've encountered before in other discussions.
And what do you know! Turns out film classifications aren't put on there just for a joke! They're actually attributed by a uniform system of criterion satisfaction! Wow, that's almost like the line was agreed on by various panels and put in place for you, so you don't need to screen everything your children watch for scenes you don't think are suitable.