My wonderful girlfriend (who no doubt will stumble across this thread) gave me a book by Bill Bryson today entitled ‘Mother Tongue’ where he says…
I always believed that it was the ‘International language of discourse’ for ALL airlines.
So who are these people and what happens when they try to land in JFK? 
I would imagine the other 11 nations don’t have any flights to an English-speaking country (maybe not even outside their own borders) and thus feel comfortable not bothering to agree to anything.
Some countries insist on using their own language for communications between air traffic control and pilots from that country. These include France and Italy - in the latter case, this bilingual (Italian and English) operation of movements on the ground was a major factor in the Milan Linate crash of Oct 2001, yet the ATC unions insist on keeping with the status quo.
As for the 11 ‘other’ nations from the quote, I’d guess we can rule out Iraq and Somalia as simply not having an operating airline, and I’m sure there’s others in the same position.
Having a working knowledge of English is compulsory for all international flights. There are 188 countries (including both Iraq and Somalia) who are members of the ICAO, the international body responsible for this kind of stuff.