The entrance of the American streamers into the factual drama space has muddied the waters in terms of defining a show’s success, according to Jeff Pope , who made his first streamer show last year. Reviews are now even more crucial than they used to be while ratings have dipped in importance in a world of cannibalized viewing, Pope told a Broadcasting Press Guild lunch this afternoon in London. Pope, an Oscar nominee for Philomena, who has made tonnes of factual drama down the decades, was speaking as he prepares to launch Believe Me , an ITV drama about John Worboys , dubbed the “Black Cab Rapist” by the tabloid press. Pope’s previous show, Suspect : The Shooting of Jean Charles de Menezes, was made for Disney+ , his first for a streamer. To this day, Pope said he isn’t sure how well that one rated, which is in stark contrast to the pre-streaming era when creators and executives waited with bated breath for overnight ratings to emerge the morning after a show landed.…