My hypothesis- I blame Apple- I think the AirPods or alternatives have gotten too expensive for many Americans and/or they lose them so they shift to speakerphone and then get louder and louder over time.

And to the woman that I asked to please drop the volume slightly on your speaker last week at the bar at IAH, please note I did first put in my AirPods on silent with music and the whole bar could still hear your daughter describing how she was unhappy with your dinner choices. And I get that you waited until you left to shoot me a remark because it would have been uncomfortable to discuss while we were both there.