Along with what I suspect is a large number of HN people, I also feel the same way. The high ideal is for people to say what they want, and we'll all think and decide what we think the facts are, and what decisions should be made.
Now, it seems to not work. It is patently the case that a lot of people simply cannot think.
One issue is that there's too much noise, as you mention. Money comes into it as well.
But underlying that is a lack of education. Western European constitutions tended to be written just about during the early industrial age, with updates up to about the mid 20th century.
That world is gone, but it left a lot of baggage for the world we live in today. In the old world, you had one chance to be educated, and it tended to be for a short period. Let's not forget that this was also a highly polarized world, where kids needed to be told which side of the great struggle between ideologies they were meant to support. So it's not as if we had a world of free thinking before the current abyss was reached. But importantly this world, especially in the West, also pretended that everyone was free to speak as they liked. We did educate a few people in how to think critically, but most people just got told what to think. If you ever heard your gran spewing out some pnemonic like ROYGBIV or the times tables, you know what I mean. As soon as you ask a question that is slightly inquisitive, there's no answer.
We had authorities back then too, and the system kept them on a pedestal, to make it easy for everyone to think as they were supposed to. The authorities got all the air/paper time, but also they made sure that the Overton window was kept a certain size.
Now there is so much airtime that everyone can have a say, and it turns out a large number of people simply can't think for themselves, because school is still pretty parochial. "Learn your times tables, here's your new opinion about helping the planet". (I don't hate the planet, and I agree with some of the things they tell the kids, but the way I see schools talk about it... it isn't thinking, it's indoctrination.) For an example, when I'm on FB looking at the US system, some older person will inevitably say "You kids don't know anything, we have a Republic not a Democracy, each state gets 2 senators". Which completely misses the point of discussing whether that's a good idea.
School never taught people how to think critically. The closest we came to it (I did the IB Diploma) was a bit of math and science, and only the fortunate ones figured out that it's not about learning a bunch of facts, it's about how humanity came to learn those facts, and how we could potentially learn more. Nobody examines you on "how would you find this out" because it's hard to fit into the industrial school system. I'm good friends with a statistician, and he says even phd folks have problems in this area.
What I see online is this world where a lot of people are simply trying their way at thinking critically. A lot of stuff reminds me of high schoolers at debate club. There's this void into which you put conspiracy theories, and people try their way at arguing one way or the other. Only thing is, they are adults with the right to vote, and with little guidance. In a way it's funny, like that flat earth documentary where the people actually buy a gyroscope and actually try to measure the flatness of a canal.
So what should we do? There's no satisfying answer. Democracy was thought up by some men-of-letters who didn't think most people should have a say. I'm not an expert but it sounds they only thought smart people should have a say. It would be sad if the only way to move forward is to beat it into people what they are supposed to think, or who the authorities are, because ultimately we want reason to be the authority, not specific people.