Can only speculate, but I assume it was partially to shield Trump for being blamed for the pretty bad economic knock-on effects of the plandemic (i.e., inflation and muh supply chain issues), among other things. Frankly, Trump deserves some of the blame for this (though not all - Fed/Treasury controls the printers).
If you subscribe to the Law of War / Devolution theory, it basically gave Trump an extra term, as Biden was "officially" the president, but Mil was treating his administration as an occupying force and had loyalty to Trump. I kind of buy this, but at the same time, the US MIL has not given me much hopium that they were loyal to Trump… I suppose they couldn't make it "too obvious", though.
Good question though, anon. Not sure anyone has a fully air-tight theory at this point.