It was a peculiar thing to say. "We don't need to give a name to anything well known! Names are for obscure concepts only, everything else can be indicated by grunting," you seemed to say.
But really your beef was with attaching a person's name to it, like an attribution?
It's from from acerbus "bitter to taste, sharp, sour, tart." So it's something said in a mildly mean, cynical, or indeed bitter way, which could include irony but doesn't have to.
Also cynicism is about dogs (and Diogenes), and sarcasm is to do with tearing flesh. There's something called the etymological fallacy that says I shouldn't explain words via their roots, but I like to anyway, I think it adds meaning.
I don't know, it's clearly a synonym to me. "Why? Are we running out of names to give out?" is clearly with the intention to be mean but be smug about it, so hence the passive agressiveness.
