Earlier quoted context omitted.
I remember when Slashdot was THE online community for tech news. Insightful comments, amazing (!) moderation system. It all went downhill years ago though and now the quality of the discussions is horrendous.
The primary issue with Slashdot seems to be the flame wars—they don’t have some of the features and the moderation like HN does to detect and prevent them. If someone mentions systemd, you know that the quality of discussion just went from “mediocre” to “terrible”.
HN has a clear vision and set of rules, Slashdot didn't. News for nerds, Stuff that matters.
Slashdot did have a moderation system where, if you were over a certain number of points (like HN) (and later hidden on /.) you could moderate. Moderation was a bit more complex sometimes leading to fun results with comments '+5 Offtopic' and '-1 Insightful'. There was playfulness. There was also meta-moderation where consensus was sought for previous moderation decisions. I don't think an learning 3rd stage algorithm would have helped, going back to the above: there wasn't a clear set of principles and very strong enforcement of that either by community of mods. And there was a very strong trolling community that were happy to live at -1, some of whom were Anonymous Cowards but have in some cases come to light as smart leading figures in their technologies.
Cmdrtaco and crew were ridiculed (sometimes very unfairly) but didn't react consistently. I don't think Dang and co wouldn't be bullied by a community site they shepherd.
tl;dr There was a special time in the internet, and some parts of the internet have learnt from this. And before this, there was another special time. And before that another. And we will look back too.