Biggest Brexit exit argument was to stop immigration.
The stopped the legal immigration all right, leading to a shortage in every low income job there is.
It didn't stop the illegal immigration though.
Short sighted is what you can call politicians nowadays.
I don't think any country could stop illegal immigration completely but it's ironic that they were able to stop or minimize the legal migration while the illegal continues. They will probably have to grant those who entered illegally like what the US is does especially when a democrat is sitting as the President.