This is an exageration . Banks, hedge funds, etc, have found in London a safe haven. Panama Files and Roberto Saviano, and others, have demonstrated that Britain financially "is the most corrupt country on earth", the most deregulated financial hub and most aggressive neoliberal economy in Western Europe. Where will banks and their associates find a better place?
“The West won the world not by the superiority of its ideas or values or religion (to which few members of other civilizations were converted) but rather by its superiority in applying organized violence. Westerners often forget this fact; non-Westerners never do.” —Samuel P. Huntington, The Clash of Civilisation and the Remaking of the World Order, 1996, p. 51