> Even here on HN, plenty of folks will comment on all kinds of research they know little about.

I don't see anything wrong with that, because all opinions are not equal.

I think there is some level of pressure to get one's word in quickly, otherwise the nebulous cloud of commenters moves on to the next story, and your well-thought-out comment that took hours to write is seen by no-one. If you're responding to someone hoping to get into a nice conversation, you're out of luck since they have no idea you just responded to them.

Any thread about nutrition is so painful here.

Anything related to medicine/biochemistry can get cringe-y pretty quickly here. I think the problem is that the crowd here is generally pretty intelligent, but they know it and it's a coefficient > 1 on the Dunning-Kruger effect