See quote from article:
> ... Since the Brexit vote and the subsequent collapse of the pound, independent food outlets of all kinds have been hurt by rises in rents, rates and food prices. Meanwhile, in families that run curry houses younger generations have moved away from catering to more lucrative jobs in medicine or tech. So long as there was a ready supply of new onion choppers from Asia, the exodus of upwardly mobile offspring did not affect curry houses too much. The real blow came when a harsh new politics of immigration came in, which made it harder for skilled south Asian chefs to work in the country, just as the wider British public were changing the ways in which they consumed curry...
> ... It is now dawning that under Theresa May’s government, the prospect of more Bangladeshi chefs being granted work visas is more distant than ever. A law that came into effect in April 2016 states that a skilled chef from south Asia must earn £35,000 or more a year, after deductions for accommodation and meals, to come work in a British restaurant that also offers a takeaway service. (The figure is only slightly lower for restaurants without takeaways.) Lord Bilimoria, the entrepreneur behind Cobra beer, is part of an all-party parliamentary group lobbying to reverse the law, which he calls “ridiculous” and “discriminatory”. No ordinary curry chef earns £35,000 (the industry average is £22-25,000 but the cooks who marinate lamb chops and mix raita get less)...
In short, while axing immigration from the EU we also made it impossible for any working class migrant outside the EU to cross our borders. I'm sure all these worker shortages in agriculture/industry/hospitality/services/healthcare/construction are doing wonders for our nations' economic growth...