All of these formerly technical terms have become re-used to the point of no return. I don't know if these are actually all the technical terms for intellectual disability, but it's an interesting evolution of language nonetheless.

Further reading on the "euphemism treadmill" - a term for this kind of thing. https://en.wiktionary.org/wiki/euphemism_treadmill

This is why constantly trying to come up with new words that aren’t offensive is fool’s errand. There will always be people looking to comment on someone’s intelligence in a negative way. If people find the act of doing that offensive, the word choice really doesn’t matter. Making up new words every few years just creates new words for people to use in demeaning ways.

The title is misleading, just like the comment from the submitter: "Mongoloian idiocy" inappropriatelly suggests Down's Syndrome has something to do with Mongols, whereas early researchers thought people with Down's resembled Mongol faces.

So while one could apply the comment to the term-treadmill on "idiot", "retard", "moron", etc, the article has no support for it and is a case of inappropriate name in the first place.