Joe Biden received 81,283,098 votes (51.3% of votes cast) in 2020 while incumbent President Donald Trump received 74,222,958 votes (46.8% of votes cast).  That is a difference of 7,060,340 votes.
https://www.cfr.org/blog/2020-election-numbers

The electoral college count was 306-232.
https://www.politico.com/2020-election/results/president/

Stories like this:
https://www.justice.gov/usao-nj/pr/postal-employee-admits-dumping-mail-including-election-ballots-sent-west-orange-residents

. . . And this . . .  https://www.washingtonpost.com/business/2020/11/05/usps-late-ballots-election/

. . . Become roots for sensationalist conspiracies about widespread election fraud and there people who run with them and start spiraling with their own paranoid ideas about subversions, machinations, and widespread Machiavellian schemes that are not based in facts.

I feel confident in saying that everyone denying the fact of the President Biden’s 2020 victory over his predecessor are going gout of their way to find specific articles about inefficiencies in our elections and using those articles to boost their own ideas about wide-scale, systemic fraud.  It’s a classic use of selection bias.

Evidence of inefficiencies is NOT evidence of systemic fraud because inefficiencies occur ANYWHERE.  Every functioning bureaucracy has inefficiencies, that is why redundant counter measures are used to catch mistakes.  However, that recognition of procedural inefficiencies and the addition of redundancies as a solution challenges the world-view which involves a powerful victim narrative of working-class Americans being manipulated by an invisible and over-arching political force.

Nevermind the reality that actual election manipulation begins long before Election Day through our complex system intertwining political campaigns with private political scientists and marketers using our televised media ecosystem to barrage the American public with what is essentially paid propaganda. Less educated Americans would rather believe more excessively simplistic narratives of altered vote counts and electoral coups happening in one day.

Humans like dramatic narratives that paint them as heroes or martyrs even when the truth is much more banal.  We want to look out opponents in the eyes and softly utter our last words of indignant deference, “Et tu, Brutus?”

We can’t all be Julius Caesar, we can’t all have the dramatic death under a statue of your enemy with thematic tones signaling a dying republic. The people who craft their own destinies, cementing their names into the annals of history, they are the exception rather than the rule. Most people are not coming after anyone else because most people are just trying to survive, but that gets boring for humans. So, we make up stories to justify our very existence. Eventually we want to be the characters we create.

Remember to ground yourself with practical knowledge periodically. If you spend too much time in your own mind, eventually your mind starts to eat itself from stagnation.