As a retired career Mil ATCO, I've learned how Americans speak and handled a 4-ship of Italian F-104s descending through the London TMA. I've coped with mispronunciation, gibberish and unclear emergency messages.
I helped run the Instrument Schools at USAF bases in UK, teaching the new guys how different things are. Our Unit even had a USAFLO to enhance coordination.
If everyone would just slow down, and realise where they are, life gets quite easy. Is that too much to ask? Or do we all sit in a oersonal space?