My reasoning for ss as voter id is just that it will be extremely hard to commit fraud against that system. Voter fraud is still a major issue and it does seem to lean heavily into right wingers, who also have a vested interest in suppressing opposing voters. And this same right wing is the one calling for third party companies to monitor votes, same right wing refusing to update an old method of voting for no reason other than “muh tradition.” The only way I can see to effectively counter that is the ss as voter id.