The answer is blazingly simple.

Every other western nation requires proof of citizenship and maintains a voters roll of eligible voters before one can vote.
The USA is the ONLY country that allows someone to vote without even a driving license or proof of identity. Canada requires two proofs of ID for example.

https://en.wikipedia.org/wiki/Voter_Identification_laws

It doesn’t matter that voter fraud is rare. Eliminate the accusation that voting is done by non citizens and dead people (by others using their name).