First, they predicted immediate collapse of the UK economy following a Brexit "Yes" vote. That did not happen. On the contrary, the vote was followed by record increase in UK economic growth and output.
Second, they threatened mass exodus from the City. It is unlikely to happen either. The City's legal status as a "Free City" above UK law, replete with "Freemen", is unlikely to be replicated anywhere in the continent....
Bankers' love of London complicates Brexit relocation plans