Don't you think that there are some people who knows (at least approximately) the total number of the printed money around the world (no mater if its dollars, euros or pounds)? I don't think we should discuss this more, because its unnecessary. I will repeat that I gave that number with the intention to show how insignificant digital money currently are, and it will take many years (if "some people" allow it, which I doubt) to be considered even a little threat to the banks/governments.
No, it's not possible the know that. It's not possible to know how many printing presses there are, or how many bills come from even a single one of them. It's not possible to know how many people are sitting with palates of benjies in their garage. Fiat is not public currency, these numbers are in no way verifiable.
Banks and governments are made of people, and people are free to use public currencies. There is no "threat" about it.