I have used Bluetooth headphones unbothered on various flights on LH, LO and SQ A380. I have flown OS but didn't attempt, remembering what their reply had been. I haven't flown LX B777-300ER yet so I can't verify that, but I'm booked to BKK later this year on LX so I'll have a chance to do it. However, the information given by Swiss on FB seems to be the same as the information you can see on their official Internet page (the link provided before) - could this be used as a reference?
Hence, I could say I HAVE got correct information from airline reps on Facebook... Nevertheless, it's just another opinion. Facts, please. Why don't you find out, using your serious academic research, what these airlines' rules on Bluetooth use onboard are. Then we can verify the information for the benefit of us all.