The really stupid thing is we have these exact same design of lights on the UK delivered Mini's, however it's just the center horizontal bar that flashes orange.

As I understand, US regulations have stricter requirements on the required light surface area. Presumably this design decision was an attempt to meet those requirements.

Audi models in the US also light their taillights in addition to the scrolling bar they have in the EU.

But like they wouldn't be any less British if they pointed the other way.

It would not match the Union Jack pattern.

Union Jack with COUNTRYMAN printed inbetween it's two halves isn't Union Jack either.