The first video shows how cherry-picked facts can be used to suggest a misleading impression of efficiency. The presenter repeats, several times, the claim that

The first video shows how cherry-picked facts can be used to suggest a misleading impression of efficiency. The presenter repeats, several times, the claim that the duct moves ten times the amount of air than that delivered from the compressor. I imagine that fact came from Jetoptera, and I don't have any reason to doubt it, but that ten-times figure is irrelevant. The comparison that matters is the rate of transfer of momentum to the external airflow, compared to what can be achieved by driving a properly- or similarly-sized fan or propeller with the same motor.