The country name thread has led to another iteration of the Burma/Myanmar debate, and its broader version: Even setting aside the special case of Burma, where the Myanmar name was chosen by the ruling junta, do we have some good manners / sound usage obligation to change the English names for foreign countries (or foreign cities) to follow local pronunciation?
I think the answer is “no,” regardless of whether the country is a former European colony. English language has long had its own names for foreign countries. My sense is that even if we focus only on European countries, the English names for the countries match the local names in only a small minority of cases. That’s especially true if we focus on pronunciation, but it’s even true if we look to spelling (for those countries that use the Latin alphabet). The same is true in Russian, the other language I know; and I suspect that it’s also true in many other languages.
The contents of each language are dictated by the usage of its speakers, not the usage of speakers of other languages, much less edicts from those governments. A country doesn’t have “a name”; it has different names in different languages, and its residents — or its government — have no authority to dictate what the name would be in other languages.
I don’t think that we have any more obligation to call Burma “Myanmar,” even if there were a popular vote by the Burmese so requesting, than we have to call Germany “Deutschland” or Poland “Polska.” Likewise, they have no obligation to call England “England,” as opposed to “Angleterre” (which is what the French call it), “Anglia” (what the Russians call it), or whatever Burmese might have historically called it. And I would say the same even if the German people voted that they would prefer that their country be called “Deutschland” in English, or if the English people voted that they would prefer that their country be called “England” in French.
Note that I set aside here questions of what might be pragmatically useful for a particular speaker or class of speakers. If you do business with the Burmese or the Germans and think that they’ll buy more from you if you call their countries “Myanmar” and “Deutschland” even when speaking English, then by all means do what you think is best for business.