It's not that they must behave one way or another, it's that there are things children just don't do in terms of word choice and behavior. Making a kid do them is one of the easiest laziest ways to convey that the child is creepy, which I suspect might have been the intent in that story if not for the fact that nobody reacts to it like that.
Beyond that, the major problem with the story would be the dumb and toxic fanon rather than the completely bonkers behavior and word choice (seriously, "Monsieur, might you point me to where I could find material on better learning the recent structure of this society?" is just bizarre coming out of an 11-year old British kid) of the story's main character.
The problem is, kids like that EXISTS IN THE REAL WORLD. I know that very well as in regards to wording, i was like that myself, thanks to being both a very quick learner, linguistically gifted and had a family that was mostly good with language as well. I did well above average on a language test meant to test for university entrance, when i was 12 or 13 for my own language, and for English when i was 16.
And in the story, it's not just that she's "creepy", it's that she's ACTING. She's trying to mimic specific "idols"(or what she believes they should sound like) she has picked up. Lots of kids do that as well in real life, even if it's with words or manners they have no clue to what they're really saying or doing. But heck, plenty enough of adults do THAT as well!
Fake it till you make it is a thing.
And again, you are supposed to rate the STORY, not who made it, not the "dumb and toxic fanon" surrounding it or whatever.
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It absolutely is relevant to the experience of reading a story when the author is participating in the thread.
There is a relevant saying; "Better to remain silent and be thought a fool than to speak out and remove all doubt", and when an author directly interacts with their fans as part of the writing process it is very very easy to remove all doubt of them being complete idiots.
Nope, that still has absolutely nothing to do with the quality(or lack of it) of the STORY. It doesn't matter if the writer is a hideous arse or a wonderfully nice genius, the quality of the story remains the same. Judging the writer instead of the story and then claim that the judgment is still valid for the story is just really bad style and really not good mental training for yourself as you condition yourself to be subjective rather than objective.
It kinda is. 11-year-olds are immature and incapable of responsibly making large-scale decisions.
When people write little adults instead of actual children, it's incredibly jarring.
*sigh*
You haven't got all that much experience with children do you?
Some children are immature. Some are not. Some flip-flops between the two and anywhere in between all the time. You can find kids of every possible variation.
Children generally lack experience, which means even mature children may not appear mature all the time because they have insufficient facts to make decisions from, this has been professionally tested any number of times, give adults and children the same level of information and then ask them to make a specific decision, and the "maturity" and "quality" of the decision is highly individual rather than based on age.
When a teacher takes on a new class of 6 or 7 year olds, it usually takes them less than a week to figure out what kids they can give responsibility and which ones they can give leadership roles. Because in every new class, there's usually at least a few of either or both.
Yes there's plenty of children "incapable of responsibly making large-scale decisions", but you know what? There's LOTS of ADULTS like that as well.
While there's plenty of kids perfectly capable of doing it. The only difference is that SOME of the incapable kids grow up to become capable.
Age does not have direct correlation to maturity. It just increases the probability. End of story.