[piasa]

For some people, saying "Bless your heart" is as sincere as saying "God bless you," and is seldom used as a sarcastic put down, at least not in "sausage supper country" where it was often said in response to someone being particularly thoughtful or generous. Of course we still used "Gesundheit" when someone sneezed, for what it's worth. Further south it seems to be used more often as sarcasm, a polite way to dismiss someone who had become annoying.

I think the idea that it is eclusively a put down stems from a talk show host or a comedian who hilariously rambled on and on about the phrase some months ago, and now it's popular among younger people.

[Gondring]

I never said it was universally that way. But it doesn’t have to be. The question isn’t whether it’s fine some places—it’s whether there are places it’s not. She’s a national figure now.