Obscene content is another matter, I’ll grant you. I do recall way back in the 1990s, in Boston, telling someone, “Excuse me, but there are kids on this train, and we can all hear your music.” I’ve heard a lot of earphone leakage in Washington, DC, but not so much obscene rap. You called the subway “Metro.” Are you in DC? Maybe it’s worse on some lines than others.
Virginia-DC, blue line (yellow or orange if there is some kind of incident). It gets even worse if you are unfortunate enough to have to take the red line East of Union Station. There are always a lot of Metro security people in those red line cars during off-peak, too, can’t imagine why.
Cue the little kid yelling "that's racist"
;^)