Oh, no, I’ve talked about this wave of that openly years ago, that comes and goes

You know there was a sibling incest vogue in the early 80s that kicked off with YA fiction? Flowers in the Attic and then a bunch of imitators, got to the point where it was just thrown into stuff as spice, like Anne McCaffrey’s “Talents” stuff.

Like, ASoIaF was a critique of the state of fantasy narratives, and a well-read fandom would have recognized Jaime/Cersei as a trope

It hooked into a lot of the then-current mainstream “yay early adolescent sexual discovery” stuff - Blue Lagoon and Brooke Shields in general - but it doesn’t seem to have left a mark, the current “step-"family porn phase doesn’t seem even aware of it

(The 70s boom was definitely aware of how they were re-enacting turn-of-the-century German trends, naturism and all, The Blue Lagoon was an adaptation of a novel from 1908)