I’d be less inclined to worry about the economic impact of Brexit if things like this weren’t happening:
https://www.ft.com/content/3dad4ef3-59e8-437e-8f63-f629a5b7d0aa
Of course there will be some advantages, as laid out when talking about dealing with Swiss enterprise, but since the EU has been and will be our more important trading partner due to geography and logistics, I am failing to see how this will be a net advantage.