It comes in four flavors:
- That group over there does X. We are not that group, so we must do ~X to differentiate ourselves from them.
- They are doing X and that threatens us! We must also do X to threaten them! Oh no, they are doing Xn + 1, we must also do Xn + 1!
- He is a very aggressive conversationalist! I must also be aggressive in order to be heard! ... It turns out we agree, but in a very disagreeable manner!
- I am working very hard, but she is not. I will reduce my effort. Oh no, she sees me doing less and now she is doing less! I'll show her how little I can do!
And it explains a lot.
https://psychology.fandom.com/wiki/Schismogenesis