[kabdib]

There's still a tremendous amount of trust involved, and many components to secure. Some folks have done security analysis of voting machines and were not impressed (an understatement). Block chains and other applications of crypto are kind of pointless if the firmware can be subverted to record Candidate B while displaying Candidate A to the user.

Oh, there are lots of technological solutions (display hashes of a vote, which can be photographed and checked, for instance). But paper and pen have worked for a long time and we have decent strategies for dealing with its faults, while the target area of a microprocessor-controlled voting machine is mind boggling.