This identity (with the minus) would be true if the only things you could do with Bitcoins were create them (at some cost) and then later destroy them for some kind of reward.
Since they can be transferred, it's analogous to saying that the amount of value produced by Visa is equal to negative one times Visa's revenue.
Since they can be transferred, it's analogous to saying that the amount of value produced by Visa is equal to negative one times Visa's revenue.