re: The Quintet from WEST SIDE STORY / One Day More from LES MIZ / We Don't Talk about Bruno from "Encanto" -- what are their musical historical roots?
I tend to think of the "Tonight Quintet" as descending less from earlier musical theatre and more from opera--the antecedent I always think of is the Act II finale from The Marriage of Figaro, which is a septet with three or four separate melodies going at once at times.