It's
especially true for ML in general on HN, but it's
generally true for a lot of areas in the public - people often mistake skepticism for expertise or knowledge.
I think the phenomenon is similar to the large crowd that cries "the sample is too small" any time statistics are brought up.
It's the first thing anyone learns, and it's easy to do.
It's really unfortunate, but that's why you see so many on HN that dismiss new technologies in ML (especially in NLP, since everyone can understand the output - that's less true in e.g. protein folding)