Stephen Sondheim (1930-2021)
Musical theater is a stagnant genre but it didn't have to be. I think I finally accepted that the medium would forever be resigned to kitsch around when Glee first menaced the airwaves. It always was a reactionary genre, a pastiche genre, a genre that gathered authentic modes into little packages and repackaged them for bourgeois Manhattanites. It's the phenomenon behind why Bruce Springsteen hits harder than Billy Joel's despite probably being a technically less talented musician. The Boss meant it, Billy only read about it in a classroom.
Likewise musical theater seems forever cursed to replicate without understanding, to gather as much of a zeitgeist as possible and polish it up. Consider Hamilton, the most cutting edge as of this writing, a show with an apparently audacious thesis: the founding fathers as hip hop badasses. It took the musical theater world by storm but did it affect the world of hip hop in the slightest? Do rappers turn to Lin-Manuel Miranda for inspiration? Certainly Hamilton's motifs references an entirely different body of music than most Broadway audiences are used to but it is still only an index, it only gestures at other things.
Sondheim attempted to use the properties of the genre to their fullest, not to simply package other styles but to convey ideas that only swelling orchestrations and belting ingénues can. His denouements, his climaxes, motifs and phrases, are all tied to *internal* conflicts and ideas. He treated the genre as literature, interested in ideas and characterization over plotting. In Being Alive the singer is compelled by the score to a lyric and musical refrain but spends half the song resisting it, he halts his singing and stews instead of going where the audience wants him to go. It is his character arc distilled musically. The Ladies Who Lunch lurches from a cool Bossa Nova, a jazzy high society interlude, into something off-kilter and unhinged as the character keeps downing martinis. We get that sinking feeling watching a friend's nervous breakdown, conveyed entirely musically. Send in the Clowns can only be sung haltingly, the orchestra may lay it on thick but the character is so upset they must chirp out banalities: "isn't it rich? Don't you love farce?" The blow of the moment, the paralysis, the inability to articulate, the external awkwardness hiding an internal storm are all conveyed musically.
Sondheim was the master of the internal because he took the genre seriously. Today neither Broadway's adherents nor detractors seem able to do that.