I could I suppose go over more of them. The point though, that I was making when I mentioned in exempting fictitious future governments, is that it can be used NOW by real governments. Sure there will be nations that don't abuse it indefinitely, but you can't ensure a governments intent 5 years from now let alone 50. There are plenty of cases I could see in some of those nations where it could be used against the people that may be less black and white, like organization efforts for the yellow vest protests being censored and removed or any peaceful protest that could get out of hand for that matter. Or maybe even Google and Facebook making anti-tech protests less visible because black bloc may show up.
"There have always been incredibly ignorant beliefs like flat Earth, anti-vaccine, etc. Usually it is isolated and the community -- the village -- keeps it in check and provides a pressure valve."
Well for one the idea of a "non geocentric universe" literally had a man burned at the stake for blasphemy, people were burned as witches, religious wars were all over the planet, so the problem isn't technology, it's humans. And I'd argue the only thing that has made us more tolerant is the freedom of information, the freedom of speech, and the exposure to ideas. Debate changes minds, telling them to stay hermits doesn't. Not only does it not change minds though, as others have pointed out, in this age, the intolerant will spread their message somehow some way.
I would also argue, that the bubble you are talking about doesn't have much to do with the ability to connect and instead has more to do with the way social media has designed their platforms. They are just like casinos. Just look at twitter. There is no down thumb, only likes and views. So you don't get the "oh you lose" social cue, you only get the flashy bling of increasing likes and views. In normal society you get a disgusted look or ridiculing laughs to tell you if you are saying something unacceptable in public. But that's not how "social" media works. And I think that specific point is what needs to be worked on. So I think we might have a common agreement in that at least. But I still think censoring is the wrong way to go. Just let the world see the true social acceptance score and I think you will see a lot of that isolation of bad ideas.