My entire life, whther while i was living in Japan, Germany, or the US, the spelling of Kiev and the pronunciation of it has remained constant. I know the locals will have different spellings and pronunciations just like cities and personal names throughout the world, but this has completely changed in the West over thw last few weeks. Now its Kyiv (Keev) vs Kee-ehv.
I know this seems small or trivial, but this is extremely fishy to me.
I think it has to do with the Russian spelling vs the Ukrainian spelling. So during the USSR Russian was of course the official language in much of the USSR and afaik that included Ukraine. In Russian its spelled Киев which is Kiev in English. In Ukrainian its spelled Київ which in English would be Kyiv because of the difference in vowels in Ukrainian vs Russian.
Until 1991 the Russian spelling would have been the "official" spelling aka Kiev whereas now you see a lot of people spelling it as Kyiv to indicate the Ukrainian spelling. Really it can be seen as a political matter, no surprise there. Sort of subtly taking a side based on spelling I suppose.
And now Russia is "the oppressor", so it is imperative to support the oppressed Ukrainians by changing how the name of their capital city is spelled.
The problem is that regardless of how the name of the city is spelled, English speakers are going to butcher the pronunciation because our mouths just don't work like Ukrainian or Russian mouths.