Good example, hop on TOR and try to access almost any image site such as 4chan as a test. 99% of endpoints are banned for uploading child-pornography or other material while these sorts of users simply look for another exit point.
The government is either ignorant about how these sorts of people actually operate, and how the internet facilitates them, or it really is a Big Brother style solution to put a full blanket audit-at-will on the general population.
Well, actually they do. At least the "end user" types.
Whilst it is reasonable to assume that pedophiles are using secure systems to transfer information the majority don't fit that profile.
The ones who do fit that profile are usually the ones creating the content for sale (that operation is extremely well organised :() and a relative minority.
the dumb ones do but they would just as easy to catch without filters or logs like this
Damn straight. In fact it's arguable whether or not we would have much more success with filtering and logs. It would be easier to secure a prosecution because you could turn around and say "well we have a log of you accessing X at Y time, explain that". But to be honest usually such things aren't needed.
The problem with filtering when pitched as a solution to pedophilia is: how do you filter for it? Oh, you could probably watch for keywords. But typing "Lolita" into Google is not illegal, so how do you figure out which traffic actually represents a pedophile downloading images? It's a dodgy path to go down; and I doubt any one of the proponents of this idea will be much impressed to find their computers seized because, say, their teenage son searched "lolita" for a school project or something :)
In actual fact the vast majority of peadophiles are caught in two ways: being reported by a friend, relative, passer by etc. OR because they tried to groom a child over the internet, and we have great success using the current logging methods to track down such individuals. Catching the gangs behind the commercial stuff; well, filtering certainly won't improve our efforts there...
[Insert nefarious reason that the people that know don't bother to inform the people that don't]