I dunno, I just see it as a sign that you don't really give a shit about talking to the other person, maybe I'm wrong. It's different when the music is being played out loud to an entire room because then the entire room has the music playing, not just the one person. But this could just be my attitude because, like I said I use music in headphones for escapism for the most part, so I guess that explains my attitude towards that, it's like shutting yourself off from the rest of the world.
Also I get the bus alone, I completely agree that you don't have to talk constantly, this video may not give off the impression but I don't actually that much, I'm more of a listener.