
Sameee, I think it's only a slur in the US.
Because apparently in the US retard = "mental retardation"- the new word is "intellectual disability". So it's offensive to those with the disability.
But yeah, I've also heard it as being used interchangeably as retard=idiot= stupid=dumb and not making fun of a disabled person. Kinda weird that retard is a slur but stupid or stuff like "shit for brains" isn't.

Yeah I understand your point.
To me the only reason it's considered a slur is because it was used as a term to insult people with mental disabilities with the excuse that it was the official terminology to refer to them.
But colloquially, its used to refer to normal people that act dumb and not specifically targeting people with disabilities.
So there's a disconnect between people who use it as an excuse to insult a specific group of people (US) and the rest of us who use it to refer to normal but kinda dumb people. (The rest of the world / second language English users).
I just personally find it funny how they are all insults but some insults are "more equal than others" lol.
The constant drop of the "r-word", fuckin kills me/neg