I have the upmost respect for him and he is sorely missed but if my bench looked like that I'd be rolling on the floor with seizures and foaming at the mouth.
It was told that Jim Williams had is desk like that so that no one could understand in what he was working on.
EDIT: If recall correctly, he didn't have an email. He attended people by phone-call or personally. So, many qualified personal, students, engineers from other companies... must have entered his office. The mess was also a diversion.
Jim Williams was no alone... take a look at his friend desk, Bob Pease.
PS: If it makes sense... those two were one of a kind