The others, I conceded, so didn't mention. Though Libération and Le Monde have certainly moved rightwards over the past thirty years, as they have become progressively more in hock to big investors.
My point is that your sweeping generalisation that journalists are "leftwing" doesn't hold good. It's an often-stated narrative meant to somehow dilute the power of big money and rightwing ideology over the press. In other words, one of the means of shifting the Overton Window.