If everyone flagged every article they found uninteresting, particularly something that rarely comes up here, because they're afraid it will become common on HN, then we'd pretty quickly have a pretty narrow and boring "lowest common denominator of interesting" site.

On a side note, I'm curious the history of "lowest common denominator". Did it start out as a confusion of "least common multiple" and "greatest common divisor/denominator" from mathematics, or was it more purposeful?