An open differential does not lock both rear wheels, allowing the power to be transferred to the one with the least traction.

https://duckduckgo.com/?t=ffnt&q=wha...=v171-1&ia=web

 

I don't have a full locker...but still days like that makes me happy my XJ has a LSD rear-end

 

Newer Wranglers do have a "Brake Lock Differential" which is kind of a misnomer as it won't fully lock the axle. It's more of an electronic limited slip system that uses the existing ABS system to limit some slip by applying individual brakes to send power to the wheels that still have traction. It's not perfect and has it's limitations.

In this instance if this Wrangler had lockers they could have did what Matt did at the start of the video and slide down to the "ditch" there then the wheels/tires on that side probably could have got them enough traction to claw their way out. Their tire choice (looked like stock tires) didnt' help in this instance either.

 

Those brake lock diffs in the new Wranglers suck for any real off roading and it will burn your brake pads up quickly.

 

And those street tires arent helping....