If that guideline is meant to cover the words “utter nonsense” it is not intuitive to anyone
In spirit, this rule should hold even if you aren't attacking the author directly but are disparaging the value of their perspective.
That is simply unnecessary and you can just refute the point directly.
How is that worse than people literally calling each other's comments bullshit on HN?
Examples: https://news.ycombinator.com/item?id=6805295 https://news.ycombinator.com/item?id=5111959 https://news.ycombinator.com/item?id=6410617 .. and many more