That is because, thinking rationally, dispassionately, and apolitically, it is a more relevant question for the incumbent who controls all the levers of power. Not for a challenger.
The Left “thinking rationally, dispassionately, and apolitically..”? Now that is funny. I think it’s just as valid to ask of Biden. They are setting up the cheat now. HRC told him not to concede NO MATTER WHAT. It’s going to be nasty between now and Election Day, and worse after.....no matter who wins.