You see how it's impossible to regulate technology? I don't want my tax dollars funding impossible missions.
Yep, that's exactly what the fed undercover will say.
And sure, they can't catch everyone, but they don't have to. They just need to catch and visibly prosecute enough people to create a chilling effect. It's about making it harder, not making it impossible.
Whether the cost/benefit here justifies those gains is a different question.