What it boils down to is this:
This debate always descends in perpetual circles of pointless tail-chasing because people fail to see the bigger picture; or to let go of their patronage of whichever language is their mother tongue.
But the simple fact is this: After we've finished winning the debate that the international language of aviation radiotelephony is English - we need to admit that it isn't actually English is it?
You heard me.
We do NOT use English as the international language of radiotelephony. We use a very simplified and restricted vocabulary of around 150 simple words, many of which have roots in the English Language, as well as some from other languages. But its not "English".
Every pilot has to LEARN the language of radiotelephony before they can use it. English speaking pilots have to learn the aviation vocabulary just like anyone else.
It's inexcusable for people to keep inventing reasons to justify why they should use some other language instead. We only have one sky and we can only keep it safe if we understand each other, because situational awareness is crucial to safety.