Getting the criminals is not the point here, mass control is. How many of your friends do this now? The criminals might do it, but why, when they can just meet in person and talk there, without a digital recording of what they talk?

Combine the 'age verification' (show your ID when you register) with this (we can read what you type), add some AI (to profile the people), and you have all the info you'd ever want on anyone anywhere.