So starting with with Roosevelt's Executive Order 9182 on Jun 13th, 1942 things changed. In July 1942 William B. Lewis was appointed as head of it's radio bureau. He had been serving as head of the Domestic Radio Bureau of the Office of Facts and Figures since he left CBS. Lewis came to radio from the J. Walter Thompson advertising agency. He made a good impression at an interview with William Paley and ended up as Director of Programming even though he'd had zero prior experience. His work at CBS is legendary and will get it's own post another day. But his connections and experience made the programming strong. It was so strong that in 1943 when they closed 53 branch offices there was a brouhaha in radioland. Billboard ran more than two pages of comments from radio program directors kvetching about the loss of service. More here.
Under Lewis the Radio Bureau became the dominant arm of the OWI at home. Abroad it had other goals but domestically it cleared network content, and created it's own for syndication. Ostensibly this was to prevent the careless leaking of sensitive information. This obvious censorship mechanism operated invisibly, clearing scripts with authority only to advise, not to stop production.however, there was also an Office of Censorship and if the OWI disliked some programming... calls could be made. But in a war couched as one between freedom and fascism, little persuasion was required. More here.
It was quiet at first, but the "war messaging" was in obvious conflict with commercial programming. It was doing harm to what had been the booming tech sector of that era. Commercial sponsors were not happy. They didn't have to wait much longer though. The Germans surrendered in Berlin in May, then Japan in September. OWI ceased radio operations that month. After it was all over Lewis went back to advertising.