IMHO, the British electorate were deliberately kept in the dark regarding the consequences of leaving the E.U.
Mrs Thatcher (whom I intensely disliked) once made an extremely insightful comment regarding a referendum on remaining a member of the E.U. She basically stated that such a question was far too complex to be put on a ballot paper, in view of the effect on all the agreements, treaties, etc.
It's only since the vote went "pear-shaped" that businesses/politicians/governments have come come out of the woodwork to warn the British people of the consequences of their "foolish choice."
Where were all these experts and their erudite conclusions prior to the vote taking place?
Is it a coincidence that French Customs Officers are going on strike before Britain finally decides to leave/remain?
https://www.bbc.co.uk/news/47454150