Comment by dragonwriter

> The monsters making these images know what they're doing is wrong, so they'll likely take efforts to scramble or further encrypt the data before uploading.

The ones that make national news from big busts do, because the ones that don't get caught much sooner and only make local news, because Google and other parties are have automatic CSAM identification online already (server side, not client side, AFAIK), and are sending hits to Homeland Security.