Biden is the most popular president ever, millions of votes more than Obama.
It comes down to a few ten thousands (or less) in critical swing states.
There's a compelling statistical argument to be made that states like Georgia, or maybe perhaps even bigger margin in FL, might have gone another way without laws & regulations to make it harder to vote and cast a ballot by mail.
My point wasn't about "who won", only pointing out the statistics of popularity, considering that an election is basically a popularity contest.
The most unpopular president (and vice-president) got more historical more votes than the last most popular president of the past 50-100 years.
You need to show papers to go grocery shopping: that's OK. You need to show papers to vote: that's not OK.
Do you see the inconsistency?
That is to say, one major difference is the availability of the papers.
The vaccine-card equivalent of Republican Voter ID requirements would be mandating that everyone present a vaccine card before being allowed to vote with the intent of discouraging eligible Republican voters.
The equivalent of present-day pollbooth security in vaccine-card form would be requiring people to associate themselves with an official vaccine record before shopping / working / etc. You wouldn't have to present an ID on the spot, but the records would be checked to look for two people claiming the same vaccination record, someone trying to claim a record that didn't exist, etc. Discrepancies would be investigated and if you were found to have fraudulently represented your vaccination status you'd be in trouble.