As discussed previously here there were specific legal and political conditions of the referendum which contributed to subsequent radicalisation afterwards. The referendum was not legally binding, with an ill defined positive proposition supported neither by the government nor the majority of MPs. This set up a situation where there was a crisis of political legitimacy. Two sources of political legitimacy came into conflict: legal and parliamentary legitimacy on the one hand, and the idea of popular will on the other. It made strategic sense for Brexiteers to try and delegitimise parliamentary and legal impediments to Brexit, provided they were ruthless enough to do so, and appeals to the 'will of the people' certainly played a role here. But appeals to the idea of the 'will of the people' was about more than delegitimising opposition. It also impacted the way in which questions about what should happen next were framed. If 'the will of the people' was the source of legitimacy for Brexit, policy would have to be justified by reference to a retroactive interpretation of this will.
This is more dangerous than it seems. This is firstly problematic because it involves not discussing one's own beliefs or desires, but an approximation of what other people believe. People are notoriously bad at this. It is secondly problematic because it does not provide any mechanism for re-evaluting a position or processing new information. Nobody can reveal any new ideas or beliefs of their own, they can only reveal new interpretations of what they think other people think. But most importantly, it means replacing the human benefits or harms of a policy as a means of evaluating it with the question of whether it is true to the spirit of an idea. It means traditional criteria of the desirability of effects and consequences are replaced with whether or not something fits an abstraction, the desirability of which is taken as self evident. It meant, for example, that when discussing whether or not the UK should leave the Customs Union, the question is often not 'what will the consequences of this be?' but 'is this Brexit?'. As Karl Popper argued, this way of thinking which diminishes the human consequences of policy in favour of their accordance to reified abstractions is a real danger to open, democratic societies.