Because people going to fast hit the breaks when they realize they are going to fast to stay on the road. They try to slow down. It’s accident reconstruction 101. No skid marks are almost always an indication of driver inattention, falling asleep or intoxication. Duh.
Also no skid marks if you hit the gas instead of the brakes.
The fact that his SUV sheared an 8" tree trunk says a lot about the speed at the time of impact.
Here's a photo showing the distance traveled from the time he crossed the center island to where his SUV came to rest. The LASD didn't give an exact measurement for the distance traveled, but did say it was several hundred feet.
Here's the tree trunk that was sheared off.