You can’t end leftist infighting by hoping for everyone to become the same kind of leftist, especially because different tendencies are often influenced by the given class character of a country. It’s why agrarian communists are more likely to be Maoists, like what’s found in the Naxalites, whereas western communists tend to be Trots. Marxism-Leninism is found everywhere, because it’s the tendency that has most been tested in real life.