Oddly there is an opera on my mind which has a similar problem, and no, I am not thinking of Butterfly although that case could be made.

I am thinking of Bizet's Carmen.

Carmen was a complete flop when it premiered, Bizet practically died of grief afterwards. Paris just did not know what had hit it. To this day, the whole thing about Gypsies and smuggling and all is problematic. But Carmen is one of the operas that sells tickets, 'gets bums in seats' to crib from the English, and keeps the opera companies in business and the opera houses open.

The Mikado is a big deal musically. Some G & S pieces are as much drama as music; but The Mikado has an ambitious score and it is long. The conductor and orchestra, spoken passages notwithstanding, have to work every bit as hard as they would in a conventional opera in which every word has music underneath it.

In the end I think it's the combination of attractive music that works in the theatre and on the stage, for both The Mikado and Carmen, which means that the public will clamor for both pieces, and we will be wrestling with the issues around each piece for generations to come.