The CBS Shuffle
CBS used to take UFOs and flying saucers seriously (or seemed to); this was back in the 1950s and 1960s.
So what happened to change the networks attitude (in the 70s up to today)?
It was the goofiness of ufologists and those who pretended to have seen flying saucers and their pilots.
More about that at our sister-site, The UFO Iconoclast(s):