How in earth can you say the evidence is against that view? The U.K. is the most successful country in the history of the world, and it achieved all of it without the EU. The U.K. has an established track record of success without the EU. It’s the EU that lacks any antecedent historical evidence of long term viability.
Maybe your point is that, in modern times, you need to be part of an “international order” to be prosperous. Australia, Canada, and Japan are stark counter examples—they’re richer than nearly every EU country and have achieved that without ceding sovereignty to an international body.
You might be too young to remember, but before joining the EU, the UK was something of a failed state. It had to go cap in hand to the IMF begging for handouts, the rubbish was piling up on the streets, and so on. Look up the Winter of Discontent.
Brexit not a choice between the British Empire or the EU, it is a choice for being run by Johnson’s SPADs rather than a sane government.
86% of the current population of the UK was born there. The overwhelming majority voted for the current Tory government and as such, for Brexit.
So therefore yes, I believe the natives are likely to bear the costs and risks.
[0] https://en.wikipedia.org/wiki/Foreign-born_population_of_the...
Snark aside, I think your comment is a useful example of a kind of patriotic (or dislike of international orders in general) motivated reasoning. Is the population of natives (perhaps citizens/residents would have fewer negative connotations?) really willing to bear costs and risks? It's a bit hard to know when there's been so much noise on the potential financial upsides/downsides of leaving the EU. Will people become more welcoming when freedom of movement is ended or does insularity have other costs? These are hard questions with difficult answers and patriotic optimism is no substitute. I'm certainly not prepared for you to assert anything about the cabinet being promising without proper justification.
All in all, I hope you're right. As far as I can tell the evidence is against you, but people survive falls from aeroplanes so stranger things have happened.