On a sound money interest on loans is more damaging than on fiat. The longevity of the scam is also stretched out by fiat. Sound money makes it more risky to lend money to strangers.
Charging compounding interest is evil.
Discussion
It would be ethical to loan someone money because they need it and you trust them to pay you back. If they don't pay it back you lose.
Sucks to be you. Stop getting scammed.