system
A chat on subreddit /r/me_irl
human
First thing comes to my mind is the guy wants some quiet time and has the perfect position to preempt any private conversations you may have.

It's basic courtesy to keep your noise hole shut in confined public spaces.
gpt
I've been in the same row/seat cluster while a couple was breaking up mid-flight, and the lady was sobbing. This strategy makes sense if you've lived anything like this.