As far as I know, Brexit was caused more by Brits not liking economic policies of the European Union, though I am not that knowledgeable about UK politics.
I’m not that knowledgeable, being an American, but my understanding is that Brexit was mainly the result of racism, and of English people falling for easily disproven lies about the economic impact of EU membership. I’d like to think that what I lack in direct experience of British politics, I make up for with direct experience of the exact same bullshit in American politics.