> Off the top of my head, I can't think of anyone who's tried to restrict people's right to borrow from a willing lender.

Didn't the Christian phase in Europe effectively restrict meaningful lending from most of the economy for a really long time?

Yes, the traditional Christian understanding of usury is right about what's wrong, but wrong about what's right. Debt based and fiat currencies in general were able to expand the money supply to allow for more vigorous growth. Gold and silver were really the only other conceivable alternatives and there was never enough of it to match the productive economy, especially after the industrial revolution. I do think that the horrors of gold-backed money are oversold: the US expanded more quickly in the late 1800s under a gold backed currency with almost no immigration, but that shows that other factors (e.g. industrialization) are sometimes more important.

The thing to get your head around is: who gets the new money? My preferred system (social credit) says everyone gets a citizens dividend, rather than banks claiming surplus value via compounding (read: exponential) interest.