Which is comparing like with like, isn't it? The USD in bank accounts is predominantly borrowed money, i.e. fractional reserve banking. There is more in bank accounts because Alice has $100 on deposit which the bank lends to Bob and credits Bob's account with $100, so now there is $200 in bank accounts but still only $100 in the vault.

Now I want to know if there is anybody doing fractional reserve lending in Bitcoin. Because if that was allowed anywhere it would erode its status as a deflationary currency and reinstitute the power of central banks to create the currency in the form of credits denominated in it at financial institutions.