It is one extra attack vector. There is a data leak reported every week, and it is now apparent we cannot trust any organization to handle any datum securely, at all. It has gotten to the point where I now consider every piece of information compromised and sold on the dark web as soon as I am forced to transfer it to a third party. Because those are the odds.
It's also replacing all the personal information stores from thousand applications and websites you have previously registered, or would have to. So arguably it's thousand attack vectors less.