“It may be red coat language.”
Maybe. But didn’t we retain the proper “King’s English”?
I had a teacher who once said that the pronunciation and accents Americans have is closer to the original English than what's spoken in Britain today.
Her point was that a people move from place to place, their language remains the same. When people stay in one spot, their language changes.
The proof of that is in how the English pronounce certain sounds. For example, whenever there's an 'ah' sound in the word, the brits add an 'r' sound to it.
So, Florida becomes 'Floridar,' saw becomes 'sawr', bra becomes 'brar,' wash becomes 'warsh,' etc.
They have other weird pronunciations, but these are the most obvious.