Immigration or the EU are not the UK's actual problems. Like in most part of Europe, the UK is experiencing a wave of populism that has one major cause: neoliberalism. Neoliberal ideology has failed to deliver economic results because it is based on the false dogma of the self-regulating market. Since the market is supposed to regulate itself and the government can only save money and grant tax breaks to the rich (which is also a form of state intervention and another proof that self-regulating market never existed and never will exist), competition between parties in terms of different economic polices doesn't exist, hence the crisis of democracy. Moreover, the middle class has been declining and feels hopeless, but because they have been brainwashed into believing that the state can do nothing and poverty is people's own fault, they need to find a scapegoat. Immigrants and the EU are the perfect scapegoat, they are actually the main hope of neoliberal lobbies and ideologues to retain their power and influence.