"Democrats are going to cheat" isn't a convincing narrative for Dems and Independents who don't already believe it.

But anyone should be able to understand that both Biden and Trump campaigns are signalling they expect a confused, disrupted election process with problems that will likely take weeks to resolve, and significant uncertainty about the outcome. Both sides are saying that there will be questions about the legitimacy of the process, especially if most of the late-counted ballots skew one way or the other.

Trump is saying that this is a bad thing that he wants to avoid. Biden is saying that this is a good/normal thing.