Trump being who he is, he can’t help using a preemptive fraud narrative to protect himself from being perceived as a loser in case things don’t go his way. He did it in the 2016 primaries; he did it again in the general election; and, of course, he’s doing it now, and thereby doing lasting damage to the health of our political system. Not that he cares.
But what will he say in 2024? What is the point of voting for him if the system is rigged to defeat him? That will surely be a problem for him, on its face.
The bottom line is that he and his followers don’t really believe in the ridiculous conspiracy theories they have been spouting for the last few months. They do, however, believe that the political, social, cultural, and economic systems are biased against people like them; that is the essence of being a reactionary. That is what they really mean by a rigged election, why they embrace nonsensical theories with no factual support, and why tens of millions of people will come out and vote for him if he runs in 2024.