I’ve written about James Murdoch’s revenge tour and deep-pocketed Gulf investors backing Paramount’s bid for Warner Bros. Discovery, and analyzed why Wall Street soured on the deal. I also write The Media Mix and am working on a biography of Rupert Murdoch to be published by Hachette’s Grand Central. Hello from Cannes, where 90-degree weather isn’t the only thing that has Hollywood sweating. France this week is the center of the advertising univ…