I don't think it's ignorance as much as "well, that won't be my child." Also, its a much more appealing alternative when it is the path of least resistance. I suspect, too, we don't really have a sophisticated enough conversation on the distributions of the outcomes. From my experience working with teens, I think it is probably the case that the media outcome of having broad access to these is strictly worse than not, but probably of a small magnitude, but that there is a long tail of negative outcomes that no one believes will be their child.