So 73% of the British people think they have a right to decide how others spend their money. Isn't that what "something should be done" means in this context? Living in post-Communist countries for fifteen years I have regularly heard Western experts explain that respect for property rights and for freedom of contract are the essentials of a free society. They are right, but even as former Communists strive towards that understanding, the battle of ideas is being lost in Britain.
The City of London is a legacy centre of excellence in an otherwise mediocre nation. It competes on a global scale, attracting talent from all over the world. It is handicapped by the poor infrastructure of London, its high costs of living and the perception (not helped by London's mayor being a fan of Castro and a supporter of terrrorists) that it is a hostile political environment. It is a filthy, unpleasant and dangerous place to work. Operating costs are high, not because of salaries and bonuses, but because of taxes, property costs and costs of compliance with (mostly unnecessary) laws. To run a big business in the City (as anywhere in Britain) you must employ many costly drones to interface with Government and regulators and to collect taxes for the Treasury.
There is no particular reason that London should be Europe's financial capital. The real City is not a square mile of land in the capital of a once-important nation. It is a collection of people and equipment which could easily be moved to any decent-sized city in Europe. If that happens, the incomes of envious Brits will suffer in absolute, not relative, terms.