Dialect coach Meier understands the appeal of the idea that 17th-Century speech patterns have been perfectly preserved an ocean away. “It is a delightful and attractive myth that Shakespeare’s language got fossilised” in parts of the US.
Not a great source honestly, was expecting more of a linguistic study rather than this. Even the article doesn’t entirely agree this is true.
English is a living language that has continued to evolve within its country of origin. Is your point that because the American dialect hasn’t evolved as much suddenly makes it better somehow?
Additionally, English is the most common language on the planet and there are many dialects, but no one outside of England can claim theirs is the “correct form of english” because it’s not their language.