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.
I mean the word will still be used as a slur by those who are rude and want to be offensive. I see this whole conversation to be about people who may have casually used the word but they generally try to be a good person who doesn’t insult and attack others. They may not have known certain words beyond some of the famous race slurs that everyone knows are bad. Non racial slurs have been more a grey area.