Well, maybe. But look at what happened when Tudor/Stuart-era English immigrants went to the US. Their language changed somewhat, and presumably new words entered the language and some dropped out, but it ossified the then-prevalent English pronunciation and many of the linguistic quirks which were current in England at the time they left. In the meantime English in England moved on to achieve its current status. Whatever that is.

Now we (non-USns) pretend to understand people from the US. It saves face all round. But actually we don't really understand a damn thing they say, sometimes!