I tend to assume that anyone who objects to “I could care less” has never lived in the New York City area. See the mention of Yiddish in the above link. But for some who object to it, that’s the issue: it’s a shibboleth of a culture they’re not part of.
I loved MrHeather's comment (who worked with Weird Al to animate Word Crimes):
https://news.ycombinator.com/item?id=22823632
MrHeather on April 9, 2020 | parent | next [–]
When I first met with Al about this project, I was quick to point out that linguists would disagree with about a third of the "advice" he's giving out. His immediate reply was "WELL THEY'RE WRONG"--really loudly in the "Weird Al" character voice.
In my mind the joke is that the song's narrator is a know-it-all character that shouldn't be taken entirely seriously. But on the other hand, a lot of educators have contacted me to tell me they use the song as a learning tool.
Have you ever traveled outside the US? I don't just mean to CS conferences, I mean really traveling.
The objections to it, though, fall broadly into two categories: ignorance, and bigotry. The former becomes the latter when someone refuses to recognize their ignorance, and doubles down on it.