if bitcoin does become a global currency between the world. how would things like loans, renting ourt apartments work? what if somebody doesnt pay back what he’s owed , can they aftually track to verify that he has not paid?
The idea of BTC becoming international currency is not realistic at all and we all know that the government won't even allow that. So the answer to your question is simple, the logic behind other service's payment systems would be the same on the fiat currency. Nothing will really change except on the currency used so If somebody doesn't pay back then the person who lends money won't receive money, and it's a clear indication of unpaid debt.