The Oxford English Dictionary has accepted idiocracy as an English word this month, noting:
The OED records more than 100 words derived ultimately from the Greek suffix –κρατία (rendered in English as –cracy), meaning ‘power’ or ‘rule’. One more has now been added to the list: idiocracy, referring to a society consisting of or governed by people characterized as idiots, or a government formed of people considered stupid, ignorant, or idiotic. Words like democracy and aristocracyoriginated in ancient Greek, but by the 18th century, -ocracy was being added to English words, as in statocracy and mobocracy. In the 19th century, the trickle of such formations became a flood, with many of the new words being terms of ridicule, a tradition to which idiocracy belongs; the earlier terms foolocracy (1832) and idiotocracy (used by Ambrose Bierce in 1909) express a similar concept. Idiocracy itself is first attested in 1967, but it owes its current prominence to the title of the satirical 2006 film Idiocracy, which depicts a dystopian future in which the human race has become extremely ignorant, stupid, and anti-intellectual.
I am not sure there is a great deal to add by way of comment on this timely decision.