I think the answer is in the Adam and Eve story. One needs the tree of life (Torah) first before one can start on the tree of knowledge (experience), because if you do it the other way round, you will be overwhelmed.
Our children need sufficient knowledge or they will find out from someone or something else, and the easiest place to get 'adult' information these days in from people who really do not care about your well being.

But I think that's only if they are sheltered from it.  Those that are exposed to it day in and day out will perhaps think its ok and later on think its normal.

this question has been discussed here on GYE in the past and many proposed the notion that the parents are better off telling the kids about the facts before they hear about it from other sources. that way they can get a picture of intimacy as being a positive, holy and special experience.

They learn about it gemora but they can't imagine their parents/rabbis doing it. Less sheltered teens know the score.

Look, if you grew up in mud and live in mud, you won't notice a stain on your filthy shirt. But if you are clean and wear white clothes... you'll notice any stain.

Once you get splashed with a little mud on a white shirt, you say, "what the heck, the shirt's already dirty, I may as well roll in the mud!!".... That's why some frum guys spiral down so fast....

Also, as they say in SA, it's a progressive disease, and as we distance ourselves from it, the disease continues to progress and we get ever more sensitive.... As Dov has written many times, he is much more sensitive today than he was when he first got sober 13 years ago. The good news is that he doesn't "test" his sensitivity any more. He has internalized that it's poison for him.

There seems indeed to be some connection between "distancing ourselves" and "sensitivity". But it makes perfect sense.

So "yes", the more sheltered are perhaps more "at risk". But that's like saying, "the spotlessly clean people are more at risk for getting dirty". Obviously.  :o