First off, this is absolutely awful to hear. I had no idea of this rampant issue in your country and I am very appalled and heartbroken for the victims.
Your question, however, is whether your government is right in banning pornography. I understand what the government is attempting to do here, I believe if you look in the past of some of these rapists you will find pornography. However, that is not the root issue. The true answer? I would wonder what home life is like. Are families encouraged or are parents split apart? Is child abuse common? What conditions did these rapists grow up in. Also, as a Christian, I believe that Jesus Christ is the answer to any solution. On a more technical level, however, I believe the government needs to work on making violators of the law pay for their injustice and then go from there.
First of all, I appreciate that you read it all. Here in Nepal, It's very unlikely that the parents are split, once they get married. Another thing, our government is very irresponsible. Today you get a rape news and the other day government gets a new law like, "You can't play horn in the valley". Government just doesn't care. And something that scares me is how every rapist has some sort of political reach to get baled out immediately or not get arrested at all. We listen the news of rape and murderer but never listen the news that the murder is caught. They skip away and that's scary to which path our country is going towards.