And this is exactly where the problem start from. Unless you are the one in control of the system, you can not trust others with you identity. For instance, people information are being traded for money from the dark web. not all these come up out as a result of hacking but people that have access to database sell this informations. In banking sectors, information about people pensions and gratuity are being altered and framed just for their own gain. This we hardly happen in a decentralized world.