If anything, it offers a counterbalance: you can also communicate with groups of reasonable people not physically proximate to you.
But now we have put all of the communities onto the same websites, and this is much more difficult.
In 2009, the NYT started a series called “Disunion”, a day-by-day look back to the Civil War 150 years prior. Filled with sampled newspapers, opinion pieces, letters to the editor.
After a couple of months, it was quite clear how a country tore itself apart. They didnt need ads or FB, all they needed were the paper owners and the editors. They actually paused the series because (imo) the things said about Lincoln in 1859 and Obama in 2009 were quite similar.
We just aren't designed to handle this and it's bringing out the worst in us.
But yes that trend seems to be slowing down, which I'd attribute to the splintering of mass media. Are we actually becoming more divided, or are we just becoming more aware of divisions because we're all more connected?
For a while the rationalist approach was dominant and media channels tended to reflect that ideology.
But with the creation of the 24/7 news cycle a whole new system to leverage the modern media tools that were created.
Eventually in the 1990s this trend came to a head with the creation of Fox news and the rest is frankly history.
But before that, for a short while, it did look like reason was overcoming superstition and ignorance.
(Trying to prune the larger sub-subthreads.)