- The Blues Brothers (1980) https://www.imdb.com/title/tt0080455/
- Little Shop of Horrors (1986) https://m.imdb.com/title/tt0091419/
Additionally to the songs, La La Land has really great cinematography and I also liked that story arc. It's more movie with songs than songs in a movie.
And it's catchy as fuck. Everybody knows the Time Warp even if you never did the silly dance.
And IMO also the James Brown scene in the church where they see the light?
And that Ray Charles demos the instruments in his store is the plot, but that the whole street is dancing along makes it a musical.