Hearing damage is cumulative and painless while it happens. Prolonged listening above roughly eighty-five decibels causes measurable loss, and personal devices comfortably exceed that.
Fit drives volume. Loose earbuds leak bass, so people compensate by turning up everything, which raises the level at the eardrum far more than the perceived improvement suggests.
Noise cancellation, used well, is a hearing-protection tool. Removing background rumble lets you listen several decibels quieter for the same clarity.
Most phones now track exposure over time. Those reports are worth reading, because a single loud commute matters less than a daily habit.