This (rather tendentious) article in The Guardian discusses the current initiatives in Iceland to ban certain kinds of online pornography. Before I go any further, let me remind readers that my position on pornography is that I am not against banning or severely regulating specific kinds of pornography if they can 1. be defined (reasonably) clearly and so be (reasonably) fenced off from the wider area of erotic literature and art, 2. be shown to cause ordinary harms in a way sufficiently inevitable, substantial, etc., to justify upstream laws – i.e. laws against activities that are relatively remote in the chain of causation from whatever ordinary harm eventuates.
I think main point of the Icelandic politicians involved is limiting the access pre-teens and young teens have to violent pornography. That access to such content is now so widespread it could be considered a phenomenon amounting to a massive and global social experiment among countries with developed internet. The icelandic politicians recognise that attempting to block violent pornography is radical (for them as a highly liberal society) and not perfectly workable (which just means that tech-savvy adults will find workarounds), so considering those things I can’t think of a better country to try it. Firstly, they probably have they most egalitarian and smooth working democracy in the world (witness the recent Icelandic revolution) which means that the blocking system is less likely to be abused than elsewhere and also more likely to be overturned easily should it not be popular. Secondly, the social data resulting from the policy will be valuable for comparison over the long term, and more so than from internet-restricted countries less similar to ours.