According to the NY Post, the Lexus rear ended the Prius ,which made a sudden stop, and he hit the Lexus. The Lexus was propelled into uncoming traffic.
The pic has been cropped, he was towing a tandem axle trailer with an off road race car on it.
I am not a fan of this creep but I was involved in an 11 car chain reaction accident in Dallas 40 years ago on the North Central Expressway and it goes down so quickly there is really nothing you can do. Leaving sufficient stopping distance on any crowded road is hard with people filling the hole you leave for yourself. Add in the extra weight of a trailer and cargo it is just an “oh crap” moment.
This is what can happen when you are following too close to other vehicles, commonly called "tailgating".