Are you sure that was a formal press conference? Doesn't look like enough reporters.
But even then, there could be a flag to the President's right. You'll notice in the photos of Bush I and Reagan, the single flag is behind and to the right, just as flag etiquette says it should be.
How long does it take to bring in the U.S. Flag on a stand
and place it next to the podium? Seconds . . .