Jack Antonoff, from Bergenfield, was always one to put his talent and celebrity to good use. Besides being Taylor Swift’s longtime producer, his band, Bleachers, has been a mainstay of pop smarts. They performed recently at the Jack H. Skirball Center for the Performing Arts in Manhattan on December 19 at the ninth annual talent show to benefit The Ally Coalition, an organization he co-founded in 2013 to help LGBTQ kids.