HN works because it is a tech forum and can ban religion/politics as it sees fit. We get lots of signal and filter out what we'd otherwise consider noise.
The issue is this doesn't work in generalist situations. Where my signal is your noise, or vice versa, people tend to do one of two things. Filter your noise, or increase their signal.
And thus goes back to the problem of giants. The noise battles we see will use every tool available to attempt to win, legal, political, or illegal. This is where splitting up the giants into smaller control zones with varied views tends to help with moderation.
Which is why I’ve taken the view that the actual solution is in the antitrust space, and not the moderation regulation space.
The problem isn’t that Twitter, Facebook, etc moderate in a way that’s biased, it’s that no entity should be so powerful that their biased moderation becomes a problem for society as a whole.