Part of the problem with this ruling is the abuse of Cleanfeed, BT's blocking system. There are a lot of people in the UK who were only ever happy with Cleanfeed and the IWF being in existence for as long as their scope was limited to the "worst of the worst", clearly illegal content.

This ruling is why, if you're going to have a system like this, it's not enough to simply say "Well, it'll only ever be used for X. Trust us." You have to go through the effort to enshrine that limitation in legislation.