Isn't that a myth?
Wonder where that idea even came from, the BBC article even says as such "“It is a delightful and attractive myth that Shakespeare’s language got fossilised” in parts of the US, [the dialect anthropologist] says."
I mean; we have old runic languages that match northern English pronunciation really well- along with "olde english" spelling which is clearly a rote writing of a southern English accent (likely from somewhere like Gloucestershire).
An attractive myth, perhaps, but I'm not sure how much truth there really is.
https://www.reddit.com/r/history/comments/bofu3g/how_did_ame...