Tell that to the people who now, instead of just going to a polling place and placing a paper on an envelope, have to download and store digital certificates, p

Tell that to the people who now, instead of just going to a polling place and placing a paper on an envelope, have to download and store digital certificates, possibly download and install new programs and deal with the troubles of all that, just so "verifying votes" is slightly easier for the minority of people with the knowledge of the system and ZK proofs. Also, you're assuming the system is perfectly implemented. In reality, such a system will be complex, will have many more pieces than the ZK system itself (and those pieces will have vulnerabilities), and will require users to do more which will also be prone to errors and vulnerabilities. I don't understand the insistence on electronic voting for elections. It's less transparent to laypeople, offers small benefits and adds significant complexity both in the implementation and use.