the missing tribute

Two days after the assassination (and one day before the funeral), a special live television program titled A Tribute to John F. Kennedy from the Arts was broadcast by ABC on network television.[62] The program featured dramatic readings from such actors as Christopher Plummer, Sidney Blackmer, Florence Eldridge, Albert Finney, and Charlton Heston, as well as musical selections performed by such artists as Marian Anderson. Actor Fredric March (Eldridge's real-life husband) hosted the program. Plummer and Finney performed Hamlet's dying speech (I am dead, Horatio) with Finney taking the role of Horatio.[63] The program has never been repeated, nor has it ever been released on video in any form.

Why has this never been repeated?