Biden is not running so this is all moot.
Trump is running. He is almost as old as Biden and the mental decline is much more clear. In addition, Trump is a convicted felon, sexual predator, thief and liar. He has many more felonies waiting to be tried for election fraud in multiple jurisdictions.
His espionage and theft of government documents case will be back shortly and hit him like a freight train, including mandatory jail time.