I agree with both of those sentiments! And as for niche communities, the challenge I've seen has been that they need a kind of critical mass in one place to take off...but at least on Reddit, that has sometimes led to homogeneity of thought and shouting down of any opinion that doesn't 100% fall in line with the hivemind.

For example, I'm a big fan of the video game Life Is Strange, and there's a major decision in that game that completely recontextualizes the story depending on which choice you make. On Reddit, /r/lifeisstrange as a metaphorical single organism has made one specific choice its accepted orthodoxy - any speaking about the other choice is downvoted and seen as blasphemy.

It's especially frustrating to me since I have nuanced opinions about both sides, seeing various arguments for each. I don't come down firmly in favor of either. But the almost-religious polarization means that my viewpoint is seen as sacriligeous because it's nonconformist, but not bold enough against the orthodoxy to be supported by the blasphemers.