If Toshi is meant to represent the average modern human, then he is a complete critique of the human condition. There are many characters in this story which can't "imagine the death of another human being", or put themselves in the place of others, like Toshi-Mon's fans or the news reporters. They are Toshi's 'accomplices' and actually part of the problem that Yuri called 'idiots with no imagination'.
By showing Toshi despair and lose the confidence he had in Mon's bogus philosophy after he manages to imagine an alternate life in which he actually talked to his co-worker and developed a relationship, we are shown that Toshi was no more than an idiot who didn't think things through, and finally came to his senses in the end, becoming 'human' (developing empathy) once more.
