Indeed, the latter corrupt ness is kind of a natural state of humanity in large enough groups that direct accountability isn’t feasible. Capitalism, including the rule of law that upholds it, is one fairly proven mechanism for addressing it (but it probably also relies on some culture of honesty to keep from collapsing back to corruption). Nonetheless, the Soviet Union lasted an extremely long time and I think people underestimate the effectiveness of industrialization. Industrialization meant the Soviet Union could last the better part of a century in spite of the problems you pointed out.

(Also, I think it’s a mistake to talk about the Soviet Union’s economy as purely parasitic on the market economies of the West... tons of science and engineering was done there and technology was developed. The Soviet Union’s system was super bad and shouldn’t be emulated but I think sometimes people go too far in saying how ineffective it was. It was effective enough to last a long time and provided a real scare to the West in terms of what system was more or less effective, at least for a decade or two... think the space race.)