What do you think that might look like?
But the five vote options (insightful, interesting, funny, off-topic, troll) were _useful_. Having a feed based on the score of votes plus friend bonus, friend-of-a-friend bonus, foe penalty, friend-of-a-foe penalty gave me a super news feed I stuck with for almost a decade.
I could see a more complex voting rule set being helpful. But basically, it was really good until it wasn't, and that was a problem of the people behind the scenes there, and not the system itself.
HackerNews is comment driven, but does a decent job of facilitating discussions - but not particularly deeply. Reddit is similar. Forums are much more amenable to linear, deep, discussion between a few parties, but can also facilitate comments. Both have their place on the internet, and I don't think that forums are necessarily the answer to everything, but it feels like a lot of people left those communities to end up in Reddit and that's a shame.
If you reply to an earlier one, the UI will handle it and show a new branch where that conversation started. I'm not a huge fan of typical mailing list web UX and usually view flat, but it's so common that I guess a lot of people like it. My opinion is probably biased from years of using/running forums, so I'm much more used to that UI.
I think newer systems like Discourse will formally track replies to you (versus a new message in the overall thread), while legacy forums like PHPBB usually just quote-reply.
It's just so blatantly, demonstrably, obvious the level of manipulation which was targeted at the sub. Somebody, somewhere, added it to a list of subreddits to be manipulated. But you can't even discuss it there, because how are you going to use a compromised communication channel to communicate about how it's compromised?
The majority of the population seemingly can't even notice that sort of communication manipulation, it's gotten so sophisticated. Bot accounts used to be much easier to detect, now they all have very cleverly built-up account history and posts that are near indistinguishable from humans. And of course not all manipulation is bots/AI, there's coordinated shill/sockpuppet/astroturf campaigns with real people being tasked with doing the manipulation.
The smart people have already left and gone on to the next place, which will never be allowed to grow large enough or significant enough without the propaganda fire hose eventually being turned on it too. The only way to fix things is a radically different framework for communication.