Does this detail matter in the large picture?
Fact is, Bitcoin is supposed to be an international currency, and we have nearly the whole world population using the metric system.
Cyprus, China, Argentina, all the countries Bitcoiners are so hyped about use the metric system.
USA and UK will have to adapt, not the other way around.
I completely agree that we should use metric prefixes for BTC. I don't like metric MEASUREMENTS, but it works for Bitcoin. Hell, even the US Dollar uses them.