Blockchain allows you to prove order in which some events happened and thus indirectly prove when such events happened (and in fact it is not some new technolog

Blockchain allows you to prove order in which some events happened and thus indirectly prove when such events happened (and in fact it is not some new technology, it is how really trusted timestamping authorities always worked). For voting you don't need to order or timestamp anything, so blockchains are mostly irrelevant.