I Imagine . . .
. . . the four horsemen of War, Pestilence, Famine, and Death, no matter the color of their mounts, are akin to the points of the pentagram, governed by the Great Spirit so there is no fifth horse of Chaos.
The young do not fully see the elegance of the horsemen yet, perhaps . . .
. . . maybe there is some corollary in the color of their mounts. Too busy putting in those driving skills to muscle memory to instinctively notice the headlights in the rear view mirror growing closer.
Night driving is like that.
As the headlamps draw nearer, growing brighter in the mirror, sometimes they line up into multiple lamps, four maybe. Reaching your hand up to flick the dimmer down to keep from going blind you just concentrate on driving, and hope they pass so the darkness of long night drives becomes peaceful again, empty, and you can flip that dimmer again to see the miles behind.