The last paragraph in the link:

But despite Google’s best efforts, new search filters sadly won’t remove child porn from the internet on their own. BBC News cites a report from Cameron’s own Child Exploitation and Online Protection Centre that explains most child pornography can’t be found through Google or Bing searches, existing instead on peer-to-peer networks or on the “deep web,” protected by anonymity software such as Tor. Without large companies such as Google acting as gatekeepers in these darker corners of the internet, Cameron will need to look elsewhere for “great brains” to continue his campaign.

Child pornography is an especially vile special case, but there is little doubt in my mind that the powers that be would love to eliminate privacy on the Internet, and not only on the Internet. I give them an inch wrt child pornography, but I fully expect them to try to take a yard.