There are ways to provide verifiability without that vulnerability. But since there's no way to prevent the wrench guy standing over your shoulder, I think you could only really solve that problem if you vote in person. If you're doing that I still think blockchain voting is great, but then you should also print out a paper trail and tally that separately. Then you have two overlapping systems with different trust properties and both must be in agreement for the election result to be valid.

There’s so much to be said for voting in person, the reason you stated chief amongst them. However, attending to the polling place on Election Day is very healthy for a community, IME. Also, there’s something virtuous in expecting people to get their shit together enough to walk in on Election Day, so long as early voting is there to accommodate those who cannot make it that day.

The rush to vote by mail (with risk of ballot harvesting, which I saw in my own city (a Republican incidentally) and online voting (with associated risks) seems foolish to me. The secret ballot, completed by oneself in guaranteed isolation, is the pillar of my confidence in our system. Pandemic be damned - it’s not a severe enough crisis (by the number of deaths) to warrant overhauling the system the night before. Feels very much like a useful opportunity to advance an erosion of faith in the electoral system. If I were Russia or China, I would be looking on at the discord with glee right now.

You can already be compelled to do that with your cell phone. People take pictures/videos of their ballots all the time (making it illegal doesn’t stop it).

Someone else mentioned a real/mask vote solution with blockchain so that issue could be solved by electronic voting.