It's true that the older and more famous a placename, the more likely it is to have different forms in neighboring languages. All languages evolve phonetically, and during the course of this evolution, the pronunciation of all words changes (independently in every language), including (especially) toponyms which were borrowed 500-1000 years ago. It's a sad misconception that if a toponym is pronounced differently, then it means it's "butchered". I think it's part of our common history and it should be embraced, not erased.
Yeah, the truly interesting part is where you make the cutoff in regions where borders shifted. Straßburg instead of Strasbourg hopefully doesn't get perceived as a claim to the place and neither should Danzig, but I'd rather write Kaliningrad because those people are so damn thin-skinned, bordering on paranoia (they might even feel threatened by the letters Sank Petersburg, even if that can't possibly mean anything other than respect). But random villages that used to have a name in a language that isn't spoken there anymore? Hands off, unless you desperately want to sound "that way" (you shouldn't!). In an explicitly historical context, you should at least acknowledge the current name.
>but I'd rather write Kaliningrad because those people are so damn thin-skinned, bordering on paranoia
In Kaliningrad, the locals colloquially call their city Koenig (short for Koenigsberg), they're totally fine with it. Although, the context matters, of course.
Nice to hear that, I guess it shouldn't be surprising that people who actually live there might be less concerned about a hypothetical reclaim than people hundreds of kilometers away. If you only know it from the map (well, that's also me) that's a what-if not rooted in reality one way or the other at all.
