Advaita (the philosophy of undivided, non-dual Selfhood) could be misconstrued as being akin to soviet style collectivism - submersion of the individual in a totalitarian state.
The Austrian philosopher Wittgenstein, like many of his generation, was attracted by both Advaita and communism. He even made a visit to Moscow to see for himself how socialism was being applied there. He was not overly impressed.
Russia, under Stalin, was far from being an ego-less state. To the contrary, totalitarianism is the total dominance of society by the single paranoid ego of an autocrat. Marx's ideals can only work if everyone in a society operates selflessly for the good of the whole, including the leader.