I'm sorry, I don't recognize your cast of heroes and villains. The 'British Establisment' - civil service, parliament, big business, academia - was overwhelmingly opposed to Brexit, and to a large extent still is. If there was any way of averting it with a shred of credibility, they would.
Here's a good one:
"The European Union has been the greatest dream realised for human beings since the fall of the Western Roman Empire"
-- the Archbishop of Canterbury (I'm not making this up).
Otoh some leftists, notably Jeremy Corbyn and his mentor the late leftwing icon Tony Benn, always favored leaving the EU. Were they in a state of abject ignorance or lying through their teeth? Maybe ...
So consider this middle-of-the-road Tory MP who voted Remain, but is now working to uphold the outcome of the 2016 referendum, NOT call another one:
"I voted Remain in 2016 and don’t regret it. But I wasn’t on the winning side. I’ve spent the last 31 months listening to why so many people voted for change. And having watched the UK’s exit negotiations over that time, my view is that we would, at some point, due to our geography, our history and our wider relationships with the world, have reached a position where the UK and the EU were bound to see their futures very differently. Once I had accepted that, I was clear that the UK would be leaving the EU."
-- Nicky Morgan, MP (Con).
https://www.telegraph.co.uk/politic...st-remainer-friends-backed-brexit-compromise/