BaggedandTagged - I wouldn't want the government to slit the throat of the golden goose. However, with a population the size of that in the UK, we can't all be employed by or directly in connection with the financial services industry, nor can those of us who can't be employed in that way all be the personal slaves of those who are. There are only so many nannies, therapists, nail technicians, private tutors, private school staff, interior designers, fancy toilet paper designers etc, required to fulfil the needs and tastes of the wealthy minority.
And doesn't it worry you to think that we might one day be marooned on an island that is totally (rather than substantially...) reliant on everywhere else in the world for its food, fuel and goods, no longer has people with the skills to be more self-reliant within its own population, and has argued with all of its European neighbours prior to pulling out of the EU? It's all very well for our island to be used like that by people with no territorial fidelities and who therefore live wherever they want in the world, but not such a fantastic vision for most other people.