The parent claim is that polarization is so bad right now because of social media and the digital media. If the press is more tame now, wouldn't that result is in less polarization?
Which leads to, polarization is not symmetrical. Some groups of society move toward extreme much faster then others.
Also, we do have less polarization then France had before French revolution.
I kind of think the warning signs are almost always only accurately seen in hindsight.