It was in the broadcast version. I have a clear memory of seeing it during the original transmission in 1979.
With this scene absent, it makes no sense for Buck to ask Wilma "Tell me about the holocaust" or to ask his home computer system "Tell me about Anarchia." He wouldn't even know enough to ask about those topics by name. Dr. Theopolis gave him sketchy information on those subjects in the missing scene, which admittedly is pure exposition but really shouldn't have been left off the DVD.