All actors are attention whores. But Williams is a man who will fucking stab a baby in the eye if he is not the absolute sole nucleus of attention for every waking moment of his life. It matters not to him if he's actually funny or not, so long as he's the loudest man in the room.
Seated next to him, how can lesser attention whores like Wilson not be irritated? Of course he'd end up resorting to half-assed suicide, the most classic of all desperate attention-grabbing techniques.