With the benefit of hindsight, it is easy to agree with what you say. But from the point of view of the scientists creating the first classical computers, classical fault-tolerance seemed just as difficult to them as quantum fault-tolerant computation seems to us. See von Neumann's "Probabilistic Logics and the Synthesis of Reliable Organisms from Unreliable Components" from 1952 https://static.ias.edu/pitp/archive/2012files/Probabilistic_...

Not that it is impossible for OP to be right, but the argument he is using used to be applied to classical computation and ultimately turned out to be wrong in that context.