Hi Ben.
firstly, I fear sometimes you misinterpret some of the comments thrown in which are aimed at being funny, on this comedy/satire site. Hence bendy bananas and Attenbrough being a higher power than the Queen.
Secondly, my recollection was distinctly a figure over a thousand pounds a head in an emergency budget, which Osborne was using to persuade people to vote Remain. Perhaps that was 'per taxpayer' which might balance those figures. Anyway, I think it is valid to say that both sides were talking about predictions, and both sides were making those as persuasive on their own side as possible. Arguments from Remain often focus on some popular print media being for Leave Telegraph, Mail, Express, Sun- but many weren't, like Times, Independent, Financial Times, Guardian and Mirror, and people will buy what they wish to read - there are enough choices and different flavours for people to select from. Incidentally, one Murdoch -owned title on each side. You may remember that TV coverage was considered to be pro-Remain, celebrities and intelligentsia were pro-Remain, and certainly that the vast majority of politicians from across the parties were pro-Remain. Also, that in two previous Referenda - on voting method, and on Scottish independence - the side with the most support from 'establishment' politicians and was seen as status quo/conformist had prevailed. There was very ample opportunity for each sides to present their own arguments, and to counter their opponents as persuasively as they could (with, as pointed out, a preponderence of the skilled persuaders on the Remain side).
There has been every sort of challenge presented following the Vote to Leave the EU (by a margin of 52:48, the same margin, apparently, that Trump has just lost the popular vote in USA). Frankly, if Trump's side were proposing some of the arguments that Remain used - that's not what Parliament meant, the vote was advisory not definitive; Parliament doesn't have to uphold the decision of the Referendum that parliament decided to hold and said they would follow) - then we would be uniting in calling Trump a stinking weaselly devious bad-loser who was seeking to flout democracy. Because it was done by polite men and women in suits with skilled oration and law suits it was received differently, but the essence was the same - don't like the outcome, seek to overturn/overrule/rerun/people's vote/set aside/decide again, or, this is impossible/dangerous/catastrophic/awful/crazy and mustn't happen. Diabetics will die with no medication (ignoring the fact that with our international reputation for supporting disaster relief, we're able to get Shelterboxes, medication, physical aid into countires at hours or days notice, so no reason to think we wouldn't be able to move things the other way. Every possible imaginable barrier or discomfort was not just erected but magnified by Team Remain as part of a concerted Project Fear campaign.
Precious little of any of it has, or will, come to pass.
The truth and actuality, I suspect, is going to be a short period of inconvenience in some areas followed by genuine opportunities for constructive growth and progress. I bet Turing will be more popular and succesful than Erasmus, and I bet equally that nobody currently bleating about the loss of Erasmus will think to acknowledge the fact, they'll just move on to the next.
Regarding successes so far: we've approved vaccine faster than any other EU country by a long chalk. PErhaps we could have done that outside the EU, I don't know but none of the other EU countries have done, they've all stuck with the EU process and equally 'held the line', there was a fair fuss about Germany starting a day or two earlier. However you wish to analyse it, we started nearly a month before every other EU country. Maybe we'd have been able to do so anyway, maybe not, but we did, and the other 27 didn't/couldn't.
Sourcing vaccines, we opted out of the EU scheme and gone for securing contracts with multiple suppliers for oversupply, and I suspect we will donate any surplus we have. That funding will have supported companies researching and developing vaccines. Some will work, some wont, so that was a big punt but as a nation we have better coverage than the EU scheme. Its unfortunate that one of the major suppliers, a French company, is going to be one of the slowest to market: I don't know at what stage that became evident but we bought a large volume of theirs too. I do know that the one EU country I know of to 'break ranks' and secure 30million doses seperately from the EU contracts took substantial political flak for it from within the EU.
Electrofishing banning, yes, I;ve totally taken that on trust from an advert, I didn't know it happened before, nor that other countries may or may not have banned it
Live-export, I'm a small animal vet so not directly involved; I do know some EU countries have banned non-stun slaughter which I get more upset about but nevertheless, I;ve had communication from senior british veterinary association and royal college figures that suggests live export for slaughter couldnt have been banned before (and is slightly problematic now re: highlands/islands and transport to NI) but can be banned/dramatically reduced now.
Hope that covers the fullness of response you desire...