>For example, it's kind of remarkable that pedophilia is considered worse than cannibalism, "meatslaves" and "woundfucking", both new words I learned today.

The first is considered as something very real, quite widespread, and very common danger.

The others are see as very exotic/extreme fringe. So it's not exactly considering e.g. cannibalism "less taboo", it's just that this and the others you mention seem to unreal and rare to warrant serious consideration. If there were cannibalism stories in the news with the same frequency it would be just up there with pedophilia