I think your vulgar derivation of Marxism ('no war but class war') has done a pretty poor job in understanding that these irl conflicts and wars are very real to the participants and not just performance theatre as you like to believe. For that matter, class identity is not the be-all and end-all, Marxist thought has done a pretty poor job in understanding that these so call "fake identities/false consciousness" such as nationalism are very real and not just something created by elites to divide the working folk and that misintepretation had real life costs in that nationalism ultimately contributed to the breakup of Yugoslavia and the Soviet Union (which lead to the end of the Cold War, but also to the current war in Ukrane).