Surest way to reduce the population of the world by one individual, is to get an EMC expert and ask them about this device. There will be a fatal heart attack right there and then.
A long wire connected to a piece of electronics, connected to a box with extremely high impedance is a recipe for much increased emissions. The most difficult devices to get emission certification on is ones with wires hanging out of them.
Further, there is no scientific data whatsoever that this device improves the sound generated by your system. User reports that is so, is anecdotal, not scientific. So in no way or shape can you use that, to say that the measurements are inadequate to validate benefits. There are no benefits until demonstrated in a proper manner.
As to FAA ruling, it was testing and measurement that demonstrated there was no danger in allowing electronic devices in flight. It was not a few people saying, "I turned on my laptop and my plane did not crash." So not sure why that story is told. It backs the alternative scenario.