I just found the theory referenced on Reddit: https://www.reddit.com/r/KidsAreFuckingStupid/comments/1tsts...
I can't explain why, but the top comment is the funniest thing in this whole episode to me:
Removed for violating Rule #6: Must be a kid and must be stupid.
Common reasons for this remove include but not limited to:
Teens are not considered kids as its a different kind of stupid.
> A redditor who's wife and her friend were on the flight said that the 16yo boy next to wife's friend admitted to naming his speaker "Bomb" long enough ago that he had forgotten he'd named it that. Wife's friend got to hear the questioning
That is also stated clearly in the comments.
Reddit really wants to run with the default speaker name theory, though.