Wow, 20% of images being misclassified as CP would be terrifying. I never thought I'd say it but my next phone will definitely not be an iPhone or any device that is uploading my information to another server without my permission for any reason.
Is there even any evidence that arresting people with the wrong bit pattern on the computer helps stop child rape/trafficking? If so, why aren't we also going after people who go to gore websites? There's tons of awful material out there easily accessible of people getting stabbed, shot, murdered, butchered, etc. Do we not want to find people who are keeping collections of this material on their computers? And if so, what about people who really like graphic horror movies like Saw or Hostel? Obviously it's not real violence, but it's definitely close enough, and if you like watching that stuff, maybe you should be on a list? If your neighbor to the left of you has videos of naked children, and your neighbor to the right has videos of people getting stabbed and tortured to death, only one should be arrested and put on a list?
This is all not even taking into account that someone might not even realize they are in possession of CP because someone else put it on their device. I've heard there's tons of services marketing on the dark net where you pay someone $X00 in bitcoin and they remotely upload CP to any target's computer.
It seems like we are going down a very scary and dangerous path.