One thing that Slashdot moderation got right is that you can’t be more than +5 or less than -1. Groupthink is much less forceful with those limitations.

A problem on forums was people quoting large comments, adding their response of "this" and then an additional signature. Digg and later Reddit moving that junk out of sight and gradually educating people not to do so was a big win.

Remote mute control was contentious in early MBone apps. Lots of good discussion about why they were useful and when.

Cisco webex went out the door with one and it's wonderfully "undemocratic" and equally useful. Just stop. Done.

Volume, hadn't thought about it like that.

There's an important distinction: raising / lowering the volume of someone in general, or just a particular thing they just said.

The good old "open discussion" at forums, as I remember it, used to manifest verbal lynch mobs, that would often target specific people instead of what they said.

The irony in me pressing the upvote button on this post…

That sounds horribly toxic and corrosive for a dinner party.

It sounds pretty useful for when you're chatting while waiting for the bus and there's someone on drugs there screaming obscenities.

Unfortunately the Internet is both.