See for comparison, "Foggy Bottom" (US State Dept.), "Hollywood" (film industry), "Nashville" (country music), "White House" (US Office of the President, or United States), "Pentagon" (US Department of Defence), "10 Downing Street" (UK / UK Prime Minister), "Westminster" (British Monarchy), "Berlin" (Germany), "Moscow" (Russia), Rome ("The Vatican" / "Catholic Church" / "Pope"), "Vegas" (gambling industry), "Wall Street" (finance), "Madison Avenue" (advertising), "Fleet Street" (British press), "Detroit" (US, sometimes global, auto industry, also R&B music), "Kitchen" (cooking/food generally), "Danish" (pastry), "Napa" (California wine industry).
Cheddar, denim, burgundy, champagne, parmesan, dalmatian, italic, duffel, lyme (disease), chihauhua, torquois, jalapeno, paisley, sherry, port, chantilley, marathon, hamburger, pilsner, balaclava, varnish, limousine and lesbian are all words originating from place names, most with generally generic descriptions (attempts at appellation notwithstanding).
Also I always thought Westminster referred to the parliament, not the crown which would more typically be referred to by Buckingham palace.
And again: the key is that the language usage is metaphorical, rather than literal.
I dispute that. I've never seen it used in that way.
Numerous other examples can be found. The meaning is often implicit, e.g.,
"Silicon Valley Needs Regulation"
This includes my own cohort of Silicon Valley professionals. A recent Stanford study involving nearly 700 “elite technology entrepreneurs”
"Silicon Valley Learns Washington’s Language (and Vice Versa)"
Big Tech’s presence in the capital is unmistakable, and its interests intersect with more and more issues, says David McCabe, a tech policy reporter.
Discussion is of Google and Facebook (both in the geographical Silicon Valley), but also:
All eyes are on Amazon and, more specifically, on its second headquarters in Northern Virginia.
That is, "Silicon Valley" is "elite technology entrepreneurs".
The notion that the only portion of the tech sector which requires regulation is that bounded within Santa Clara County, or Santa Clara - San Mateo, or the SF-OAK-SJ MSA, is clearly absurd.
Tim Harford at the BBC:
"Silicon Valley stands for cutting-edge technology, bold ideas that change the world."
etc., etc., etc.