@Satsuma
> someone listening to audio can distract a whole room, while someone using a laptop or smartphone is relatively unobtrusive

I get your point, but maybe this depends how easily distracted you are? I recently spent most of a 14 hour flight desperately trying to tune out all the other screens in my peripheral vision, and keep my eyes focused on the video I was watching. That's what got me started thinking about #EyePhones (visual equivalent of noise-cancelling headphones).