I heard a quote from a friend, maybe from his MP or something, not sure, but he said that he believed sin disguised as good entertainment is just as dangerous as pornography. I don't know if I agree with that completely because no one ever became addicted to Will and Grace or whatever show you want to substitute, but I think he's barking up the right tree at least.
The Book of Mormon teaches by repetition, and when people repeatedly see the same things being reinforced (homosexuality, fornication, adultery,) and the negative consequences aren't taught as well, I think resistance to the thing wears down.