This topic (erosion of consensus reality) is one of the most interesting things happening in the world right now, with implications that are hard to imagine.

I wonder if it will have weird parallels to antiquity, where propagation time (e.g., physical travel) was so slow that cultures were incredibly distinct and varied; except instead of long propagation times, now you have instant propagation, but people are inhabiting entirely different mental spaces due to tribalism, affiliation, etc.