Not having read Twilight, not sure, but I have some guesses, and take these for what they are worth, which is not an awful lot at all. Take these also with half a question mark at the end.
1) Twilight got recognition after the Potterdammerung, and perhaps that vein in adult readers of YA can only be mined once.
2) Similar production values does not mean similar outcomes. Rowling and Meyers may be comparable writers but their books are quite, I'd imagine, different. There might be differences in style that make one more engaging to adults than the other.
3) Potter's POV is a boy, Meyers' POV is a girl. Both of them display reasonable facsimiles of average gendered/age behavior, and for some unfaaaaaaathomable reason, readers find one set of behaviors more irritating than the other.
4) All wish fulfillment is not equal; I might argue that being a special snowflake because you have magical powers and a great destiny appeals to more ages/sexes/sexualities than being a special snowflake because a pretty magical thingamabob decides you are their soulmate. OTOH, to test that, we'd need to pair Twilight off with a Magical Girlfriend series to make sure that, again, the wish fulfillment is not constructed to be highly gendered (and not to skew the data before the test, but I have a conclusion and therefore would not be the best one to test it).
5) Girl Cooties.
6) On the other side, I've heard that the Twilight books promote some very fucked up relationship and gender dynamics, and while the Potter books have some fucked up dynamics (relationship and gender dynamics, no less) a lot of them are kind of mitigated by the fact that the POV characters are other than us, they are magicians, and a lot of their creepy dynamics involve use of wish-fulfillment power. Bella is a normal human being and her dynamics involve being in a relationship with a controlling, jealous person (with super powers, who sparkles).
no subject
1) Twilight got recognition after the Potterdammerung, and perhaps that vein in adult readers of YA can only be mined once.
2) Similar production values does not mean similar outcomes. Rowling and Meyers may be comparable writers but their books are quite, I'd imagine, different. There might be differences in style that make one more engaging to adults than the other.
3) Potter's POV is a boy, Meyers' POV is a girl. Both of them display reasonable facsimiles of average gendered/age behavior, and for some unfaaaaaaathomable reason, readers find one set of behaviors more irritating than the other.
4) All wish fulfillment is not equal; I might argue that being a special snowflake because you have magical powers and a great destiny appeals to more ages/sexes/sexualities than being a special snowflake because a pretty magical thingamabob decides you are their soulmate. OTOH, to test that, we'd need to pair Twilight off with a Magical Girlfriend series to make sure that, again, the wish fulfillment is not constructed to be highly gendered (and not to skew the data before the test, but I have a conclusion and therefore would not be the best one to test it).
5) Girl Cooties.
6) On the other side, I've heard that the Twilight books promote some very fucked up relationship and gender dynamics, and while the Potter books have some fucked up dynamics (relationship and gender dynamics, no less) a lot of them are kind of mitigated by the fact that the POV characters are other than us, they are magicians, and a lot of their creepy dynamics involve use of wish-fulfillment power. Bella is a normal human being and her dynamics involve being in a relationship with a controlling, jealous person (with super powers, who sparkles).