Caudillo, if we use your logic, we'd all need to pick up some "basic aviation" Mandarin, Japanese, Spanish, Portugese, Russian, Arabic, Hebrew, 'merican
etc. - for the two or three trips per annum each of us
may do into each region.
As for the post above saying a common language is only needed when it's necessary (???): who's to dictate when it becomes necessary?
I'd like to suggest that when we're all scooting about the sky between 150 and 450 knots,
even if the use of the second language doesn't cause confusion and reduce SA (which few I think would argue it doesn't [but I see above that there are some]), it causes unnecessary delay.
(How many people have waited, waited, waited for the French language version of the CDG ATIS to do its loop before listening to the English language version - when they could be doing something far more productive in an often very busy environment?)
It's even more counterproductive when you hear ATC and another aircraft conducting a (sometimes long) conversation in French that
may (how are you to know?) have some bearing on what you should - or should not -be doing.
Someone's said it already. The French cling to speaking French because somewhere deep in the French psyche they've never quite come to terms with the fact that the days when French was the accepted top of the rung 'international' language are long gone.