The tree is a tree where people got lynched on. The murdered are buried underneath the tree. The shadows of the audiences hand represent the dead bodies reaching up at Kanye, who himself represents maybe another victim hanging from the tree, or even be representing a god like figure the dead are reaching up for.
Ima be straight up with you, this is so artistic it is mind blowing to me. Every other performance had flashing lights and everyone jumping around stage, while this was simply left on one frame and performed in one place while trying to get a message across.