Interesting, thanks for the info on that. I was on an international Air Canada flight last week and they specifically announced that nothing wireless at all was to be used during the flight, including all headphones.
EDIT to add the official policy: "Air Canada is happy to announce that, beginning on April 1, 2018, passengers on our flights will be able to use their personal headphones (of any kind) on our in-flight entertainment system or their personal mobile devices. This service is available from gate to gate at any time, except, of course, while the safety video is being played. Please note that wireless or Bluetooth headphones may be used only on flights with WiFi, because of their technology."
Confusingly I think this means that you can only use wireless headphones with the 'provided entertainment' when the flight has Wifi because that's how they get their entertainment to your device. If the flight doesn't have wifi you have to use the in seat entertainment system and therefore can't use wireless headphones (because the entertainment system doesn't support them) not because you're not allowed to have them enabled.
https://www.faa.gov/news/press_releases/news_story.cfm?newsI...
> You can also continue to use short-range Bluetooth accessories, like wireless keyboards.
I use my BT headphones when traveling all the time.