Having been on that line often, I wonder about the reporting here (especially NY Post). Pulling into Grand Central is not really the time you would be arguing about noise, as you are about to disembark onto a noisy platform, that will offset the “music”. Thinking that there was some other beef, going on.
“Pulling into Grand Central is not really the time you would be arguing about noise,”
Maybe the issue started earlier. The prime time for an attack would be just as you pull into a station.