But 'Song of Norway' had Florence Henderson and Peer Gynt! 1965 was the watershed year of sorts. the Pawnbroker came out which was the first mainstream film to have nudity albeit in a very serious context (about Holocaust survivors). The Sound of Music and Doctor Zhivago were hugely popular and could not be duplicated. Even by their own directors (Robert Wise and Julie Andrews tried it again with Star!, David Lean with the disasterours 'Ryan's Daughter' the failure of which pushed Lean out of film making for over a decade.)
But conservative Hollywood kept trying with one Julie Andrews musical after another and more big budget historical epics ("Battle of the Bulge", "Tora, Tora, Tora", although they struck gold with "Patton"). Poor Darryl Zanuck couldn't make a star out of his squeeze Irina Demick or dig himself out of "Cleopatra". Was there a Broadway musical they left unfilmed ? The Right lost control of Hollywood because they lost their audience with the collapse of the family market.
I wonder though, whether the moralistic Irwin Allen disaster movie was a continuation of the Biblical epic. Didn't they all have a "Jeremiah" scene where the prophet pleads with them to follow him to the truth but the crowd angrily refuses (like when they wouldn't climb the Christmas tree out of the ballroom) and is smitten for their sin ?