But UK (and London especially) is different - that's why they left the EU and were always in tention with EU when they were a member, especially with regards to their financial sector. Bay Area, New York, Austin, US has a decent number of hubs, London is most comparable to New York from my experience (I've worked in a London based startup, NY agency and a SF startup) mostly focused on financial and not really into hard tech.
The U.K. left the EU because of left behind towns blaming the EU for their problems.
London (like Scotland, Liverpool, Manchester) voted massively to stay in the EU. Other gentrified cities like Leeds, Bristol, Oxford, Cambridge also voted to remain.
Where is your evidence that leave was driven by London doing things differently?
The UK is different, because the EU is not like the US federal government. Economic systems and cultures vary massively across the EU, far more than across US states. Hell, half the EU were Marxist-Leninist autocracies just a few decades ago!