Sloppy law-writing has always been a pet peeve of mine.
Like the Pennsylvania law that makes it illegal to drive with excessive amounts of snow on your car (but fails to define “excessive”, freeing every traffic cop to make up his own mind on the subject and fine you).
The failure here is Congress’ for failing to define what that meant.
You don't think that's intentional? Make it look like we're doing something, only to get struck down by SCOTUS, but they can turn around to their constituents and say, "Hey, we tried!"