So your stance is that the author is just wrong, and men were just as committed to marriage in the 1950s and 1960s as they have always been, and nothing changed until the 1970s?
My stance is the author said it STARTED in the 1950s - not that marriage terms or marriage rates had declined significantly in the 1950s. The significant declines in the marriage rates did not occur until the 1970s when they really started declining. Several sources have said that.