SilverWook said:

As with MGM, somebody lacked the vision to see what a tourist goldmine the old backlot could have been.

20th Century Fox stockholders went nuts after the studio backed a number of box office disasters in the 1950's. The back lot was mostly used for Westerns, and the land value was shooting up in that area that is adjacent to Beverly Hills. By the early 1960's, Westerns had fallen out of favor, and T.V. was taking hold super fast. The studio needed cash fast to pay off debt and also finance new projects to please stockholders. The studio head refused good advice to take out loans, and the land developers were knocking their door down. Fox also had other location properties (such as Malibu Ranch), so they sold out about 75% of their Mix Ranch studio property with hardly any thought. If they would have been able to hold out with the advised financial loans until 1972, "Poseidon Adventure" would have revived the studio fully, and paid the loans off.

A 1988 photo of "Hello Dolly" street, with a very new Fox Plaza ("Die Hard's" Nakatomi Plaza) in the background. This street is the only remaining purposely constructed out door set piece to still exist at Fox's (Mix Ranch) studio.

Now with MGM, they wanted to get into the casino hotel racket in Vegas, and literally lost the farm.