We can really only take loans against crypto until the fiat money system collapses.
We can only do this because fiat is taking all the inflation.

When the Fed lends $1.00 you need $1.10 to pay it back, but the 10¢ doesn't exist
So you have to borrow another dollar to pay back the original loan.

We will find very quickly that in bitcoin, there can be no usury.
But, we will also realize that a bitcoin in the future is more valuable, especially if it is lent out to make the world more. (more bigger, more better)