This is not true. Most seats have a 120/240v receptacle that can keep laptops charged while in use.
You’re forgetting this thing uses a mostly passive M2 chip. Not to mention I’m sure they designed it so it could be powered from the USB c ports on their laptops. The headset won’t use anywhere near the amount of power you seem to be implying.
That's voltage, not amperage. Just because it's a 120V receptacle doesn't mean you can draw large current. My laptop charger gets booted off the grid pretty frequently on a full plane.