But why on earth would anyone borrow Bitcoins at present when you can get a Fiat loan for interest that's lower than inflation?
Prissily, not a good idea to borrow Bitcoin's at the moment, unless you can sucker someone into lending them and default.
But I think the point was you can lend and borrow any amount it is not limited by the total supply. (and it has been tested despite the risk)
Seems a waste of time to empirically test the obvious. The question is only: Is Bitcoin the cheapest way to borrow money. At present, the answer is NO. A few years down the road, when Bitcoin is in the 4-digits and value increase is in the single digits - and inflation in the FIAT world is deep in the 2-digits, the situation will change because nobody will give you a FIAT loan if inflation can at any time get into the 3-digits or higher unless you pay outrageous interest.