Most people speak/understand more than one language and English continues to be the lingua franca. Only North Americans speak only one language (and that poorly), even my taxi driver in Kuwait spoke/understood 8-9 languages. We assume that English will be spoken/understood by everyone and speaking louder will help others understand what we are saying.
My most recent taxi drive involved a driver who spoke English, Urdu, Hindi, and Russian (it was in Brooklyn). Multi-lingual taxidrivers are fairly common in most metro areas. When I lived in the Caribbean for a year I noticed that my friend, who owned a small dive shop, spoke with moderate fluency the languages used by customers: English, American English, Canadian English, Italian, German, and a little French. This kind of thing happens wherever is becomes an economic necessity. What I'm curious about are things like logbooks (and eventually c cards) written in languages like Mandarin Chinese. No chance of easily translating things like Kanji script.
The acceptance of English as a lingua franca has, I think, seen its high water mark, and will slowly diminish as time passes. Perhaps not. We'll see.
It's true thar most Americans are militant monoglots, and that many cannot understand why foreigners persist is using those strange bizarre languages they learned as children. They should outgrow them, and learn English. If English was good enough for the Bible to be written in, then (etc., etc.)
The talking louder approach is most successful when accompanied by extravangant gestures and repetition. Failures of this system are not infrequent.
