But it's still Moscow, Russia and not Moskva, Rossiya. It's Tokyo, Japan not Toukyou, Nippon and Germany and not Deutschland. If you're going to drop exonyms, you should at least do it consistently, rather than only for currently-trending locations.
The main difference is that the request to change the English spelling from Kiev to Kyiv came from the Ukrainian government. As far as I know Japanese or German government haven't requested that we stop writing "Japan" and "Germany".
The closest current example going on right now is the Turkish government wanting to change the English spelling of their country from "Turkey" to "Turkiye".
It went beyond official names of cities. Supermarkets actually changed the spelling of the Chicken Kiev to Chicken Kyiv. (But left Bombay Potato and Chicken Madras unchanged, even though Bombay and Madras haven't been called that for decades.). Zelenskyy probably has better things to do right now than dictate the spelling of breaded garlic chicken fillets.
> As far as I know Japanese or German government haven't requested that we stop writing "Japan" and "Germany".
Because they know it would be silly. Do they go to every language and ask for a change? For instance ask France to stop using “Allemagne” and use Deutschland instead? Now repeat for hundreds or thousands of languages… not only would it accomplish nothing, it is pretty disrespectful to demand of the other language users how they refer to places.
In the examples you list, AFAIK, people from those countries are happy to use those names when speaking in English. At least, I've never met a German who insists on calling their country Deutschland when conversing in English. If they did, maybe things would be different. That's the way it is with Istanbul/Constantinople, and also Bombay/Mumbai.
Allemagne's name is appealingly populist, though I suppose not much different from how all the "primitive" tribes' names also just mean "the people". You might even eat Allemansratten there -- though you might do better in their northerly neighbor, where the traditions lived a little longer. Eat it next to the hearth on Freya's-day.
One version of your question that's interesting to me is that of translating people's names, rather than countries'. This seems not to be what people do -- but why not?
There are the obvious correspondences across European languages, like with William and Guillermo. But I suppose a tweedy old Brit named Reginald could even become Rajesh when he visits Delhi, given the shared meaning and etymology. He might take to it happily.
I suppose you're generally better served by keeping your native pronunciation, so long as the people around you can more-or-less say it, because it will be more unique in your new location, and give you some appeal of the exotic. In England, who would you reckon to be sexier -- "Katherine" or "Katerina"?
Some names can be translated in meaning, but there is no shared etymology. For example, the Frenchman "Pierre" might take the name "石" ("Shi") in China. Would this make sense? There is the added complication that the latter is more likely to be a surname than a given name. I wonder what Dwayne Johnson thinks.
If there is no pronunciation at all for your name, you may become "formerly know as Prince" (there's Raj again), deposed by choice and deadnamed by necessity.
I suppose direct translation was commonly done with Native American names. We remember "Sitting Bull", not "Tȟatȟáŋka Íyotake". On the other hand, we remember the Patuxet man nicknamed "Squanto" -- given name "Tisquantum", you can see how it's a longer form -- and not "spiritual power of Manitou" (the exact translation is sketchy, but the meaning seems to be something like that). And of course, "Manitou" can also be translated, so we might even say "Power of God". Perhaps "Manitoba" is "God's Country".
Allowing semantic meaning to penetrate an ethnic boundary may be fraught with controversy. Here you're playing with sacred words. Of course, after studying the Greek Titans for a while, you realize that each is simply a noun. Gaia is Earth. Chronos is Time. They are not separate characters. They are the ideas. So maybe all words are sacred. Yet here I am spelling them.
Likewise "pho" is just "soup", but outside Vietnam it's more than that. Likewise "chai" -- at home it's "tea", but abroad it's a particular style of tea. Likewise probably every food there is. And they become jealousy-guarded totems of identity. "What is patriotism but the love of the food one ate as a child?", asks Lin Yutang.
Or, should I say, asks "forest language temple", or perhaps, "sacred forest library". (Nominative determinism much?)
I would like to meet this German who insisted on saying only "Deutschland" though. I imagine he would also insist that anything with more than the Reinheitsgebot's 4 ingredients is not "beer". He would drive a Volkswagen and brag about its double-clutch. He would be a great character. I'd watch that TV show.
Do anglos read Kiev and Kyiv particularly differently in the first place? In any case, it sounds further from a normative Ukrainian pronunciation than Caillou.
I read Kiev with an /ɛ/ sound, and Kyiv with an /ɪ/ sound.
In my head, at least. I've just realized that I haven't needed to verbally refer to this place since I became aware of the renaming. In fact, I don't know that I've ever said either one out loud.
Why is this an instance of the phenomenon? Isn't Kyiv closer to what a Ukrainian would say?