I should be more specific. By "peaking" I mean a local optimum rather than a global optimum. I would liken it to the reaction of, say, the civil rights era. Put another way: the civil rights era (particularly desegregation) caused a reaction by those who resisted progress and sought to reinstate their desired social order.
What we've seen in the last 10-20 years is a similar reaction to improvements in the rights for various minorities. Combine this with poor material conditions and you have a recipe for reactionary attitudes and violence.
There are many parallels between now and 1930s Germany. The Great Depression hit Germany hard so there's your declining material conditions. One of the earliest targets of the Nazis was what's likely the world's first transgender clinic, Berlin's Institute for Sexual Research [1], complete with book burnings. We also have increasing nationalistic sentiment, currently with the completely invented anti-immigration crime hysteria.
Also in common: this idea of moral decay. Then with "cultural Bolshevism" [2], now with "cultural Marxism" [3]. And the Great Replacement [4].
What's required is a normalized belief system and the right material conditions for this radicalization and polarization to spread. Social media is, well, a medium. It cannot replace or create either of those conditions. It's like blaming radicalization in earlier times on the existence of the printing press.
[1]: https://www.hmd.org.uk/resource/6-may-1933-looting-of-the-in...
[2]: https://en.wikipedia.org/wiki/Cultural_Bolshevism
[3]: https://en.wikipedia.org/wiki/Cultural_Marxism_conspiracy_th...
[4]: https://www.reuters.com/world/us/what-is-the-great-replaceme...