There’s a clear campaign against the mentally ill with the global rise of fascism. Lots of it shows up in anti homeless rhetoric, but you can see it in the MAHA and anti vaccination movements.
There’s no reason to use the word “r-tarded” to describe someone. As someone who’s worked with the intellectually challenged, it’s an insult to them to compare them with people who are willfully ignorant.
Oh oh do the n-word!
The n-word isn’t going through a continuous euphemism tread mill, unlike how r word variants continue to go through. That, I think, makes it substantially different — though in truth it’s the same for it as well