While, yes, someone probably could arrest a few child predators (defined as someone who actually abuses someone, extortion counted here) by spying on everyone (and they have), the numbers are usually fairly small compared to the inflated statistics.
Something on the order of dozens. Maybe, over a hundred, in around a year. And that's like two billion people on a platform.
That's the number the advocates of authoritarianism come up with.
How many murders are there in a city? Do we search all the houses for corpses?
They usually go on about a "thousand cases in ten years", although they usually leave out the time range and instead opt to say "a thousand cases".
That's around a hundred a year.