The early internet did #3 much better than today. I'm still a member of a ~50 member forum that's been going for 20 years, and the ability to discuss nuanced topics is much better than it is here, even if the average quality of the persons themselves are much better here.
A key reason this is because of "weirdness budgets". If I independently arrive at a solution and try to communicate that to you, the more work it takes to verify(so I can easily tell you some prime factors, but not say uhh.. UFOs exist) the result and the more different it is from your prior, the less likely it is to succeed.
This is magnified by the n ( n - 1) / 2 cost of communications, where n is the number of people. We all have different norms, and it's nearly impossible to work out where another persons norm is within a single comment, so mostly people surpass your weirdness budget and you ignore them.
This means that we can only meaningfully talk about things that the general public are on the same phase of. This is just another way to state the Overton window. But now that we understand what creates the Overton window, we can attempt to evaluate what we can do to mitigate it.
Now when we evaluate Facebook, reddit, YouTube comments, HN, message boards, BBS, and 1720 Venice coffee shops we can see them for what they are. The more you bump into the same people, the more nuance you can find. Nuance is where the insights really come from. No one can work it out themselves.
Another depressing reality is that when you do find a tight-nit community that is able to create these insights, all you have done is segmented yourself from the general public's Overton window. Now your just another weird LISPer, and the Java programmers that have libraries and drivers behind their projects will run circles around you even though you are correct. Correctness isn't enough.