I "hear" ya. I had several Brits ask me if I needed a passport when back home in New Mexico, and when I lived there, had many people mistake my British-born GF for American, and me for British.
As for Audiophile, there has always been equipment and aficionados in the US, just not mainstream, or affordable. Manufacturing has been driven out of our country since the 60's, so what is manufactured here is stratospheric in price and availability, and everything else is made elsewhere, so can't really accurately be referred to as "American". Prior to the advent of the transistor, we had a thriving Hi-Fi industry. Miniaturized electronics killed that, as they were cheaper, and never going to be mass-produced in the US. Even so, the Hi-Fi community lived on, it was just driven "underground", so to speak. America has been the primary mass market in the world for many decades, and the consequences are mostly negative.
As for the unwashed masses doing things like considering BA reference quality, I ran into that in Britain just as much as I have anywhere else in the world. It's human nature to have easy biases and assumptions, nationality or geo-eccentricity is just the flavor on top.
As an example, I think many Brits are understandably proud of the Automotive history in Britain. Having owned and worked on a fair number of British cars, I could easily classify the entire lot as rubbish, based on my experiences with gear boxes and anything having to do with electronics or wiring! However, in spite of all that I still dearly love the Spitfire, several MG's, and the Mini I owned, as well as the Sierra RS Cosworth I lusted after but never acquired. Conversely, I could have judged the RS Cosworth by the anemic XR4ti we had available in the States... which was a flaming pile.