What are the choices on offer? UK has a productivity and aging problem.
First productivity. If UK citizens refuse to work for min wage how do you think reducing migration will help productivity when wages rise? Higher pay for less work. This simply means what ever is produced will be less competitive. The currency collapse will only have a one shot benefit. If you are not exporting than everything that is produced will cost more for other UK citizens to purchase.
Just saying by stopping migration we'll raise wages and not expect anything else to change is nonsense.
Secondly, the aging issue. Increased tax burden and greater NHS and many other bills associated with aging. Once again health care support workers are much in demand. I know from experience. UK citizen simply not stepping up to the plate.
Builders might enjoy Brexit stopping decent builders from abroad coming in and in most cases doing better quality work at lower prices. However, this means rest of population will lose out paying more for less quality work.
Then there is the skilled workers to consider. Simply means jobs requiring skills will move; much like in medicine or finance or legal professions. Not only will they go to where the skilled labour is, European countries are giving inducements to attract these industries.
Then there is the other side of the coin where skilled British talent will go abroad too. The economics of the argument doesn't hold water.
We are not just simply competing with our neighbours for work. It's a global stage. We are competing with rest of the world.
There is a flaw in the free market argument for movement of goods and servivces as well as capital but not for labour. It will skew your model.
Reason why EU works so well is precisely because all factors of production are free to move withing borders of the common market. Whilst that market place is protected in a controlled way.
Still see lots of foreign cars on the roads. So WTO tariffs not excessive. EU model is clearly a success, so much so that the rest of the World is moving towards similar practice.
Then there are what's called national strategic industries that EU protects. UK pays no heed for these industries and the people who talk about open markets don't really give a toss about migration, as long as it gets them elected. Every freaking Tory party and Foreign Minister has promised a reduction and yet we've had increases.
Would you say that's just bad management or deliberate intentional policy driven to maintain productivity growth whilst bearing pressure preventing wage increase? It is clearly the latter but some may well disagree.