The Herald article mentioned above reflects one view. Others will present different views. Immigration was an important factor for many people in the UK. The UK is not against immigration, but many do not want uncontrolled immigration from the EU. This is causing real pressure on services, e.g. the National Health and state education in parts of the country. Two possible reasons for the current situation is that the UK may be viewed as having a successful economy and that English is taught in many EU schools meaning EU immigrants can have a working knowledge of the language on arrival. This would not be the situation e.g. with migrants from southern Europe going to northern mainland Europe. The intransigence of the EU on freedom of movement has become a step too far for many in the UK.
Brexit is complex and compromises will have to be made - no-one wants a lose/lose result. Bad for companies in the UK could be bad also for the likes of BMW, Peugeot, Volkswagon, Citroen, Fiat and the other industries that have significant exports to the UK. Europe also benefits from UK human expertise, just as we do from theirs. Let's see what happens after the initial posturing is over and the real negotiations are conducted.
Jonathan