Culture has a way of seeping out of a country and embedding itself into the global consciousness.

Regardless of how you see "Modern Britain", global denizens will only have so much space they apportion in their brains to worrying about British culture.

Those things which stick tend to be exactly as OP describes.

If BA wants to avoid "culture clash" and general confusion it would do well to pay heed to the world's expectations on what "British" means.