You are missing the point. You're allowed to think highly or lowly of whomever, for whatever reason. That's your business (freedom of thought). It's more problematic when you express, overtly or not, such low opinion, as you will cause resentment. And there is the risk that the mere request is seen as a "correction". In our society, it's not generally polite for adults to correct other adults' speech.

I would also take issue with reasonableness of the request. You concede it does not offend you, and that it's merely a preference. I also have a myriad of preferences about speech: the intonation, accent, the grammatical constructions, the words, etc. To ask of other people, whom I don't even know intimately, to match my preferences is something else altogether. It's to impose my preferences over that person's dialect or ideolect, which is also rightly frowned upon.