It's hard to believe a person of high IQ is not going to be well-read and/or well educated.
The only point about this test is it's specific to native speakers of English, but if you were born in North America than it surely applies to you even if your parents speak another language.
> It's hard to believe a person of high IQ is not going to be well-read and/or well educated.
What of high IQ individuals who are born into low- or middle-class families, who didn't have their parents read them 19th century British novels, and therefore don't know what a dowager is?