There is an intermediate until full robotization. That is, when robots are efficient but not that much. So, I wonder who will pay the debts when robots/smart algorithms become more and more advanced. With people being jobless, companies won't have to whom to sell stuff. There is the suggestion of "basic income", but in this extreme case, it is merely printing money, it won't circulate with enough quantities to pay enough, well, basic stuff. Not even companies will find ways to invest, since their products will not yield profit, since there is nothing beyond the basic to buy them. But, even if people slowly use the basic stuff to buy some products, all the debts, and worse, with growing interest, will not be pardoned.
So, in this intermediate stage, I think people will get despair and there will be a societal collapse, if the debtors simply do not forgive debts. I see some of the sort of stuff happening nowadays. Many of the advanced countries are injecting money, but a quite large portion of it is not used for investment, but it is simply hoarded for especulation (futures investiment). It looks like a vicious cycle. Japan, it seems, it is using negative interest, but is not working well.
