This is not true if the voting apparatus is separate from the identity of the voter. There are two ways to accomplish this, and the USPS is proposing that they

This is not true if the voting apparatus is separate from the identity of the voter. There are two ways to accomplish this, and the USPS is proposing that they ship voters a sort of "private key", which is fully anonymous, which has no connection to their identity. This key is used once, with the right to cast one vote. In such a system, the whole blockchain will know what each public key voted for. The difference is that there is no connection between this public key and the vote of an individual. This would allow for a massively snd openly auditable system, without sacrificing privacy or convenience. I am not a proponent of this, as I think that in the near and mid-term futures, there are too many technical problems to be worked out. If, however, we end up giving every citizen digital ID cards as Estonia has done, and using those as secure hardware used for voting, we could distribute the voting process. Essentially, there would be no more vote-counting. There would only be vote casting and the election results would be apparent to everyone, immediately. Consensus is absolutely necessary for such a system.