Public User said: "Instead of "feel-good", I think you are talking about women belting out their determination to withstand all odds sort of thing. For some reason, it just doesn't have the same qualities when a man tries to sing them, probably because men traditionally have had the upper hand for so long.
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I think it's because our culture allow women a broader range of emotional expression than is allowed to men, and the same is true of female v. male characters. This has changed somewhat since R&H. See "Dust and Ashes" and "Waving Through a Window" from the same season.
As William Goldman once wrote about movie characters, especially from the 1950s on: men DO while women FEEL. The latter often makes for a bigger song.