I will say that, at least in the US, I don't think you can be convicted for possession of CSEM on a hash alone. They have to prove that you really have what they think you have. And if it comes down to it, if you have to defend yourself in court, these stories of hash collisions, if true, will help your defense if the prosecution can't cough up the actual files that you had. But IANAL.
We'll see how this goes, I guess. But I just can't get as angry as some people over it, at least not yet.
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