> back then, American English was a foreign language and was just as difficult to understand as spoken English in one area was to someone living in a far corner of England

As now we have "tuned in", in the main, to voices from people from most parts of the world (I did have a completely incomprehensible removal man from Glasgow when I fist moved up here, but that is by the way)

Perhaps, to disagree with myself, that standardisation has relaxed it's onward march. In the same way that my children are bi-lingual - street Scottish at school and plain(ish) English at home, many of us can understand (and often speak) several varieties of English.

So in the Flicks we get sanitised, clearly enunciated Disney mixed in with Al Pacino's Godfather and Ewan McGregor in Trainspotting or Robert Carlyle in "The Full Monty". (I wonder how many people understood all three films).

So now, not only have the accents become less deviated from the mean but our understanding has expanded - so we are all now polyglots!