To be transparent, I looked up what the preferred term seemed to be because I didn't know offhand and I wanted to offer actionable advice. Most resources seem to recommend "person with intellectual disabilities" ("intellectually disabled" being the adjective form of that, although I could be mistaken). The NIH doc recommends “learning disability” specifically to be used in place of the r-word.

So yeah, I'm also happy to use a better term if you know of one. I’m not really trying to prove a point here, per se — I just know there is widespread consensus that the r-word is a slur and I’m trying to gently help us move past it :)