I'm trying to say it's contextual, and so I disagree with the post saying that "jobless" or "psychotic" are ableist even when not used as such, since it's completely arbitrary if you see words that way. I would say that psychotic and retard trip the line enough for me to not use them (although I have not ableist friend who use it as a synonym for stupid), but that's mostly down to how it would come off to most people, stuff like crazy or stupid are fine to say, imo, since they're basically only used to mock how people act.

I'm not sure I got my point across well, lmk.

Also as a note, I agree with your example, but cracker would be a slur if it was used against a white minority in a country, and many languages do have equivalents that are slurs. It's also not really an insult, the only people I've seen get offended by that are snowflakes.