Well, on a personal level I quite liked Laos.
no, my point is that if the uk actually restricted immigration to only Western Europe plus Canada/america/NZ/australia then
the universities would go bust (they have massive numbers of international students from China, Middle East, India, Pakistan, etc)
the nhs would implode (even faster than it is at the moment) as many nurses and doctors are recruited internationally - Kenya, Pakistan, India, Nigeria, Ghana, etc
social care would fall apart - many carers in nursing homes and who drive around doing home care are again, Indian, Pakistani, Eastern European, Nigerian, Ghanaian etc.
agriculture would really struggle - I live in the fens and there are gangs of Eastern Europeans who do the harvesting and come into the country on temporary agricultural visas
etc etc