Opening the industry section of Swiss doc festival Visions du Réel , with her latest Netflix-produced feature “Cover-Up” serving as the festival’s opening film, Oscar-winning filmmaker Laura Poitras pointed to a documentary sector that is not only under pressure but increasingly mobilized – including around opposition to the Paramount-Warner Bros. Discovery deal. Citing an open letter signed by more than 1,000 industry professionals, she said: “There’s recently been a letter calling to block