I can see the argument for this but it also has to be considered that many Ukrainians are Russian speakers and many of these are also proudly Ukrainian. I wonder whether insisting on the new spelling/pronunciation might have the unintended consequence of alienating some from their Ukrainian identities.
It is always difficult to compare language situations but Swansea are not called Abertawe in the Football League. The supporters who speak English are no less Welsh than those who speak Welsh. Using Russian for Kiev/Kyiv does not immediately seem to reduce support for the multilingual country of Ukraine.
Language and the invasion of Ukraine
There has been much talk that the capital of Ukraine should be written in the style used in Ukrainian Kyiv rather than the Russian Kiev - see, for examplehttps://www.theguardian.com/world/2022/feb/25/how-to-pronounce-and-spell-kyiv-kiev-ukraine-and-why-it-matters?CMP=Share_iOSApp_Other