Sounds like the FTC needs a programmer or two on his staff. What’s needed is a global “do not email” list. Signing up for a similar measure regulating telephone spammers has cut my calls drastically. This would be trivial to implement, particularly if the FTC charged a nominal fee for the service.
Heck, I can write that code for $100,000, easy. How much money will be spent just talking about the problem???