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.
Abraham Lincoln famously said “Free those fucking n****rs”, right? Okay, actually a LOT of the politicians and white people of that era were ridiculously racist but that is why things continued to boil over until the 60s… and then continue on since then.
But yes. A huge part of things IS behavioral. And the language people use is a huge part of that. Because when someone says “Hey, that word is a slur and is hurtful” and the response is “Fuck off, I am not treating you like property so be happy with what you’ve got”… the behavior is pretty abhorrent as well.