It also happens frequently on economic topics, especially regarding inflation and monetary policy, which seem to be fertile topics for conspiracy theories.

It isn't just finance and economics, although I totally agree with you that they're especially bad. The forum has become too wide in scope and started attracting the usual online idiot horde that dominates all other sites already.

You can see this even in tech. Most of the commenters have been handed incredibly powerful database / IDE / computation tools which makes them think they're very smart to be playing around with it. What they don't realize is high level tools are not meant for people who want to understand the tooling. They are meant for users of the tools whose task is something else entirely. So you get folks who don't understand how a simple race condition would occur or something else very obvious to folks who have done a bit of low level programming, but they will hold forth on mutexes and locks as though they invented them.

Any idea why it's weekends? That's presumably when those who are actually working have time.

No idea. I can't even say if it's the lack of high-quality contributions and meta-moderation, or an over-abundance of low-quality contributions.

The patterns I noticed mainly revolve around certain topics.

Interest rate and monetary policy articles on HN never produce productive discussion, for various reasons, which are quite obvious if you scan the comments of these types of articles so I won’t elaborate on what they are.

I quite often write and post a comment to correct a misconception and just end up deleting it because the person I am replying to is going to dismiss what I am posting anyways. Now I don’t waste my time.