The thing is, everything in this world is now gauged by engagement, not quality. The fact that this is getting more reactions on HN gives it even more exposure, and actively reinforces this behavior even more.

If you have a really good, thorough study that is so thorough that people have nothing to comment on it, it will not rise to the top of pretty much any platform, because comments are valued higher than upvotes on most platforms. So you want to engineer some clickbait in there so that your article gets madly commented upon; being incomplete is perhaps the easiest way to do this. (I don't know about HN, but it certainly appears Facebook and Twitter work that way.)