including in her late thirties but looks nineteen and nineteen but mature for her age as warnings on a fic is unnecessary and tasteless (though i’ve never personally seen any fic with such warnings) — but i have some stuff to say about the other arguments made here.
the majority of fics in this community are written by women who are in or around their twenties. in real life — and indeed, in fiction — this is a vastly transformative and often tumultuous time, when it feels like actions mean everything and consequences mean nothing. the attraction to writing about this period of life is not borne of some invisible ageism that OP wants to accuse these women of — rather, a desire to capture the fleeting feeling of recklessness and passion. that’s not to say these traits don’t exist in forty, fifty, even sixty-year-old women — but naivety and frivolity are much more commonly found in young people.
aside from this, i also feel it is important to note: strangers on the internet who post their creative writing as a hobby, owe you jackshit in terms of the reasoning behind their characters’ ages. she’s nineteen because the writer made her so. she’s sixty because the writer made her so. eat it up or close the tab.
i’m sure nobody needs reminding that literature has always been a vessel through which to explore and understand the world around us — and the world within us. some writers may use fic as a way to process something that has happened to them. some may use it to reclaim something they feel has been brutally stolen. and some of us are simply hot for inappropriately older men, and are seeking some way of exploring that without facing the real-life consequences.
because here’s the punchline: we are not some softball coach caught grooming underage girls. we are women on the internet, having fun with fantasy and exploring sexuality in an enclosed space where we are safe from the very men you’re accusing us of parroting.
it’s hurtful, shameful, and frankly repulsive to pass the responsibility for men who do actual real-life harm, to a group of women which most likely shelters survivors of those types of men. it’s just finding new, creative ways to blame women for the evil acts of men. we cannot be hurt here. we cannot cause hurt here. that is the very fucking point of what we’re doing.
in fantasy, real-life values mean shit, because real-life consequences don’t exist. takes like these, on the other hand, only ever serve to further eradicate the spaces in which women can safely explore their sexuality, free of judgement and free of harm. and that is a very real danger.