The tire rock quickly stopped rotating due to the VERY high transverse, crosswise, net friction force overwhelming the longitudinal net forces of the right side and left side of the granite rock. The dive down visual effect is the change of forward kinetic energy to rotational kinetic energy about a moment arm from the pavement surface to the car's center of gravity. In the curling scenario, this slightly higher front edge load increase is very minimal due to the very low friction factor of ice on ice with minimum rock slowing friction per unit time. The friction is only slightly higher on the front edge of the tire rock than the rear cup edge. That force adds greatly to the friction component resulting from the fact that the load on the front edge is larger than the trailing cup edge.
Drag vehicles have wide tires.
Remember your bicycle days. Wasn't it easier to drag the rear wheel over the curb than bump over with the front tire. The very fact we are on a pebbled surface causes the tire rock and granite rock to vibrate. This vibration causes a pitching motion with leading and trailing edge hopping up and down increasing leading edge friction. This is GOOD .