The Heritage Foundation has a lovely site dedicated to documenting election fraud convictions.
www.heritage.org

Even a cursory review will make a few things obvious:

States average about one conviction per state per year.

The vast majority of fraud by voters occurs in what would be considered "red" areas. (eg, Western Kansas)

The majority of fraud ISN'T COMMITTED BY VOTERS. It's by what I call "the three Cs": Canvassers, Cullers, and Counters.

The reasons for so little fraud by voters in Presidential elections are obvious:

1. You'd have to be voting in one of 6-7 states. That knocks out ~80% of America: who in their right mind would commit voter fraud in Idaho or Connecticut?
2. Each fraudulent vote is punishable by 1 year in jail and $10,000. Hardly worth it.
3. Fraud at scale is only as strong as the weakest link. As we've learned, you can't have 4-or-more people involved in a crime, without at least one of them posting something on Facebook. And if it were rampant...where are the whistleblowers, where are those with a change of conscience, where are the deathbed confessions? This is where Macro turns into Micro: if not a single person has come forward, that's because IT DOESN'T EXIST.
4. Speaking of, if ballots were grabbed by roommates/housemates/lovemates, we'd have testifiers coming out of the woodwork, especially after a close election, and ESPECIALLY if they believe that usurpation contributed to Trump's loss. Not a one, when the theory demands tens of thousands?!? DOESN'T EXIST.
5. Voter impersonation is near impossible: disguises, changing in the car, detailed research on who votes, odds the person you're pretending to be will have voted, or might be known to the locals; travel between precincts after 2-3 votes (at most) per location, etc
6. FWIW, in the last election, there WERE a handful of fraudulent votes. In all the cases I read, exactly ONE involved a Democrat.
7. IIRC, one of the 60+ cases ended when the judge asked how many of the questionable votes went to Biden. When the lawyers hemmed and hawed, and suggested that's not the point, the judge forced them to admit NONE of the questionable votes had gone for Biden.

Did you catch that last one? Trump's lawyers were arguing, Yes, we lost, but our side committed irregularities, so you should throw out the valid results, and declare our guy the winner.

In related news, Trump tasked Kansas' Kris Kobach (KKK), to find all those illegal voters. If you recall, he's the moron who claimed he had "100 cases ready to file" in KS, and after 4 years and $4 million, had exactly 9 convictions: most from super-red western Kansas by folks who'd moved across the CO border, and one (count 'em, ONE) illegal. Well, Kris's national task force was disbanded after they found NO fraud, and issued NO report. FOI requests eventually revealed they never turned up a single instance.