Ultimately the issue with anti-contact arguments is that most people today consider themselves to be "sex positive" - meaning they believe that the expression of sexual desire is not inherently harmful, In fact they'd say repressing that desire is harmful. This was not the view of our society formerly, which held that desire (sexual desire in particular) is something powerful and potentially dangerous, and thus needs to be reigned in.

Our society has claimed to be sex-positive while retaining much of the same instinctual feelings about sex as before. Youths are confusedly taught that masturbation is normal and healthy, but that porn is bad. They can masturbate, but they cannot go into a sex shop to buy a toy to do it with. They're taught that having sex with other youths is normal, but that it would be harmful with an adult. When prodded, people will apply rationalizations that will be equally hypocritical if questioned further.

Pro-contact is the logical conclusion for those who view sex positively. For those who would argue that sex is harmful, the idea of restricting the knowledge and experience of sex is justifiable. I'm not making a pro-contact argument here, merely applying the Socratic method. Right now my personal views are undecided.