Obviously, Trump’s premise that he is being prosecuted by Joe Biden because he is running against him is false. Trump is being prosecuted because he is a career criminal, and there is no evidence any of the prosecutors taking him to court have communicated with President Biden.
But beneath this first lie, there’s a second lie: Trump only intends to prosecute his political enemies because they did it to him first. In fact, Trump has been planning to lock up his political opponents since he first ran for office, well before any of the current prosecutions began.
I think his whole mission is "get elected, pardon myself". He will do this in the most shameless way possible to highlight the fact that he "got away with it".
People around him are probably sick of explaining state vs federal and all the other things he gets wrong.
I also think he's just got an SOP to delay any legal proceeding by default.