The reason he has been stripped of his title is political. We are in the midst of this controversy over bankers bonuses which the govt has taken a lot of flak about so at this point in time making a gesture like this makes it look like a banker is suffering.
He is a sacrifice to try and make it look like bankers can't get away with their actions. It is an attempt by the govt to look tough on bankerrs and to deflect the focus away from bonuses and any reform of the bonus system.