Both Lenin and Mao didn't deploy a Marxist system. They did deploy an autocratic system under the guise of Marxism. At best, we can speculate that autocracy is

Both Lenin and Mao didn't deploy a Marxist system. They did deploy an autocratic system under the guise of Marxism. At best, we can speculate that autocracy is a failure mode of attempts to install Marxism. That's the problem with all social theories - running experiments on them takes darn long, usually results in piles of disenfranchised and/or dead people, and is in no way repeatable. (Frontier Thesis kind of addresses that by insulating the core of society from the experiments harsh results, but... you still have harsh results)