Keeping children safe and prosecuting are too different concepts, only vaguely related. So no, being able to track pdfs doesn't make children safer. What keeps them safe is teaching them safe communication habits and keeping them away from things like Tiktok.
We shouldn't make the world a worse place for every one because some parents can't take care of their children.
>Keeping children safe and prosecuting are too different concepts, only vaguely related.
See also: That time the FBI took over a CSAM site and kept it running so they could nab a bunch of users.