Edit: I'm from the Global South, I should've clarified that on the post. The lesson has been learned.
Many leftist movements, legit or not, call themselves either Trotskyist or Maoist and keep dissing Stalin for his “socialism in one state” policy and “ruining” Comintern and Deng Xiaoping for his “liberal” policies.
I want to know what they are trying to do by distancing themselves from the USSR and PRC while fetishizing Cuba and Vietnam—you'll only hear them talking about the Vietnam War, btw—and following either the guy who lost the power struggle or a literal Marxist-Leninist who supported one of the refused countries and founding the other.
The USSR was the birthplace of the revolution and the only socialist state in the world at the time. Of course they were central to the Comintern. They had the most power to materially affect the course of world events.