This is because (as I think you implied) HN, in a show of consistency with other online forums, is fond of reaching conclusions that are contrary to (any) conventional wisdom. This is a source of bias: I'm a current Googler who thinks Google is great, but this opinion doesn't change anyone's mind.

But this bias is a good thing. It causes internal disagreement, hindering solidarity, but it increases the rate at which we learn new things.