How?

The wedge is already driven between skilled professionals who can compete on the international market, and therefore have price-setting ability, versus people who have no market power and can be squeezed and threatened with the unemployment regime. Unskilled or marginal workers may end up starving.

No, this is the Greece effect. Trade balance has been terrible for years. Now the financial services industry is under threat. While there's a lot of negative things you could say about them, at least they've brought in foreign money to keep the accounts balanced. In order for the balance of trade to recover, imports have to fall. This means that the part of your living standards which depends on imports (including Azure) is going to fall.

And unlike countries that can export home-grown food and/or raw materials, most UK exports are the end of a long supply chain that starts outside the country.

So even on exports, its margins are a lot lower than those of countries that produce raw materials and food.

Brexit will make this worse.

The UK can't continue like this indefinitely (it's not the hegemon, like the US) because when you spend more than you earn you have to make up the difference by borrowing money or devaluing your own currency.

The consequences are predictable - prices rise, inflation rises, the cycle repeats, and eventually the economy breaks down altogether after sovereign default becomes a real threat.

At that point the UK will either have to go full North Korea, or will need to strip everyone of their savings, raise taxes - and will still need a bailout.

Having "taken back sovereignty" the country will be on the hook to the banks for decades.