My apartment overlooks a city of 1 million people in the UK - I estimate generously that 50,000 of them are economically productive in the sense of producing something of value that can be 'exported' from this city. The other 950,000 must live off that value - it doesn't make sense. All factories are flattened to make way for apartments. Any industrial development is of distribution centres for breaking down pallets of imported tat.
I don't know what this will lead to - perhaps it's the collapse of the Euro, the rise of some stable currency that isn't playing this game, or an opportunity for a new currency (crypto or something that we don't have yet).
Just as the LIBOR scandal revealed that commercial banks were just making up numbers, so I believe that central banks are doing the same with each other and trust will need to be removed from the system.