I feel like most people would like Vulcan frankness, until they were on the receiving end of it lol

I don’t actually like that bit of dialogue, but it was (I believe) written before it was shown that Spock had a human mother in Journey to Babel. But even then… Vulcan understanding of logic should also give them an understanding of why someone would find such a piece of frankness insulting.

In fact, his father wouldn’t be a diplomat if Vulcans didn’t understand such things.