The concern is that adding another barrier to voting directly equates to more voter suppression.

We already suppress many voters here in the states; from gerrymandering to polling location shenanigans if there is a way to keep non-whites from voting the republicans will take it. We don’t need to give them more tools to shape the outcome.

You already need to register to vote with an address where your ballot gets sent to, and your name goes on a list for your polling location so you have to check in. There’s no real need for a new formal document.