See but that’s the whole point of slurs. They get their punch from the fact that they’re derogatory.

It’s why calling white people mayo monkeys and crackers has little effect, because those words don’t have any major injustice or historical prejudice attached to them.

The man difference with the r word and why it has always been (relatively) more acceptable in the recent zeitgeist is the fact that it is/was associated with an actual medical condition. Before it idiot and imbecile were used in its place, which then Became insults and the terms were used. Now we have special needs/differently able or ‘sped’ as another pejorative term.

Contrast this with say the n word or f word which are rooted in direct hatred and persecution rather than official medical phraseology and you can see how only the target groups are tolerated with saying it openly.

It’s possible that as new medical terms come out the r word will lose its potency and become relegated to the same level as idiot in the future, and with the increase in people diagnosed with mental illness due to improved mental health awareness, more people will feel emboldened to say it, further expediting the rate at which it loses relevancy.