How do the costs of our current dominant model of currency change at scale? Seems to me the cost-per-unit drops as the currency foothold expands, based primarily on existing infrastructure.<p>Conversely, costs to "mine" bitcoin and similar proof-of-work currencies increase over time, unless I'm mistaken. The infrastructure is already in place, so it seems absolutely bonkers for costs to go up at scale.<p>Is the argument for bitcoin that in the long run (hundreds of years), with bitcoin the global currency and no longer being mined since it hit the cap, costs will on average be less than bills/coins/credit/cheques?