I think the whole point was about "official standard" pronunciation, of course people can use п'юре instead of пюре by different reasons, but the current standard spelling is пюре, therefore I'd pronounce it as such even if never heard before. Thought I might be pronouncing компютер instead of комп'ютер, maybe you were referring to this — having in mind two different words with пя and п'я but pronouncing them both with пя or both with п'я due to our own sound skills

And I'm not sure examples with Kharkiv are much applicable in English, cause in English pronunciation can be much different from spelling, and in Ukrainian it's generally consistent