Paper ballots can be printed easily. There are no security standards built in. Your checks have watermarks and printing styles that make traditional duplication on publicly available machines almost impossible (to do well)
Money has tons of built in security measures.
Why wouldn't Americans use one of the many methods of document security to prevent fake ballots from entering circulation late in the game
Let’s use paper I would be willing to give a thumb print in it to personalize it plus the purple thumb method?
paper ballots are racist.