I should've referred to Traction Control for sideys. The control system will reduce engine power and apply the brakes to specific wheels that may be slipping. Whilst performing a sidey the car is extremely sensitive to any change be it momentum or direction The resulting change can cause the car to move suddenly when side sloping and that's very dangerous.
ABS stops the wheels from locking and allows us to steer, on a normal road, but we're on sand, and sometimes gravel. Sand and gravel under the tires act like tiny tint balls when you step on the brakes. As a result, there will be very little friction/traction between tires and ground. Therefore, all four wheels want to lock up immediately. ABS would keep them from doing so. You will keep rolling on and on and on and on.