The National Film Board of Canada said Tuesday that Tom Perlmutter is stepping down as its chair and as the government’s film commissioner as of Dec. 31. A release on the NFB website said Perlmutter is leaving his role “to devote himself to thinking and writing about the long-term issues affecting the arts and public cultural organizations.” Perlmutter said in the release: “This is an ambitious undertaking which I believe I am uniquely qualified to take on and which I am convinced is fundamental to the future well-being of the country and its cultural agencies. But it is not something that can be done as an adjunct to my current work.” The release said Perlmutter will stay on as a strategic adviser to NFB. Perlmutter has been with the NFB since 2001 and...