I had the same question. Typically, loans are inherently trustful, because the bank has to trust to get the money back at some point. And if the debtor does not want to pay, there is (hopefully) a working justice system to make them pay, which is also something the bank trusts in.
Right now you can get a DeFi loan at places like changenow.io that don't even require you to sign in. You put up crypto collateral. When you pay back the loan with accumulated interest you get your collateral back. If your collateral drops in value to 50% of the loan amount, you lose it and are released from the loan.
This all happens via distributed execution of a smart contract. No banks or governments required.