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.
You’re comparing apples to oranges. Attempting to change “homeless” to “un-housed” is different from just not using a slur — you’re assuming that non-derogatory terms don’t exist for neurodiverse people; there are no “improvements” to be made, just exercising some discretion. You shouldn’t be using slurs just because it’ll turn acceptable soon or because everyone else is using it; if there are people that feel hurt by it and have a history of being marginalized by such usage, you don’t have the right to use it; that is if you are a morally sound person that doesn’t care about BS buzzwords like “political correctness”.
So you are about language policing.
Go pound sand.