Skeletons riding skeleton horses underwater have broken pathfinding when strafing

Skeletons riding an undead mount cannot pathfind correctly underwater causing them to swim in one direction, making them incapable of pursuing the player. Use the following command to summon a skeleton horse trap:

/summon skeleton_horse ~ ~ ~ {SkeletonTrap:1}

Other than the ridiculously high speed, the skeletons on the horse swim in a random direction away from the player.