The state owning the means of production means the people running the state have a shit ton of power. Just takes a handful of bad people to turn that into oppression as we’ve seen in the USSR and China.
If you disagree feel free to explain your reasoning.
Corruption is a matter of individuals rather than the form of government. Any human system is bound to be corruptible since it involves humans.
I think a strong anti corruption culture is the best defense against it.