I'll bet I've read a hundred articles in the last four years-- news and opinion pieces-- that mention the fact that Trump's taking of the blue wall in 2016 was by very slim margin and that if only a small number of voters had changed their minds in three states, Clinton would have won. 2020 is even closer. Had Trump won AZ, PA, and GA, he would be president. He looks to have lost them each, assuming he indeed has, by a whisker, not to mention NV and WI being very, very close as well. By the "how many voters would have needed to switch in key states" metric, he came closer to winning this one than Clinton did last time.
The problem for Biden is that unless he apologizes for his own and his party's constant demonization of his opponents as racist and sexist and actually manages a "Sista Soldja" kind of rebuke to the Woke Left, he will remain toxic to conservatives and the divisions will solidify.