If that "man up" were scaled to percentages of body weight lifted the body builder wouldn't have got up off the mat. He was lifting a much lower percentage of his body weight but really struggled.

It's your classic functional vs non functional strength argument. The bodybuilder excelled at the non-functional stuff and the BJJ guy excelled at the functional stuff.

These type of vids don't prove much except that training has to be specific to your needs and goals.

The body builder trains to get big and the BJJ guy trains for real world functional strength, both excel at their respective chosen fields.