Successful socialism has only formed with Marxism Leninism because we understand a state has to be able to defend itself from imperialists. Libya, Bolivia, and others fell because they failed to defend themselves. I don’t see why this is a problem. The USSR and China have achieved vast improvements in quality life and technological advancement all while having collective ownership. The USSR’s degeneration and dissolution are truly tragic, but they can be avoided like China has. Marxists study the mistakes of the past and adopt what works. China realized they could thrive without a strict planned economy and they now have the largest economy, which unlike past largest economies has defeated internal poverty. Are you saying just because mistakes were made it wasn’t even worth it to leave feudalism for socialism?