I agree with your overall sentiment, but those concepts are hardly java trivia. I think the intent of that article is to use those questions as a 0-pass filter

I agree with your overall sentiment, but those concepts are hardly java trivia. I think the intent of that article is to use those questions as a 0-pass filter. You don't hire based on getting them right, but you damn sure don't let them pass to the next phase if they get them wrong. Like FizzBuzz.