Earlier quoted context omitted.
Those lines are from a song, and a significant part of the audience at the time wouldn't be listening in their native language; it's not really a fair comparison.
? It was written in German for the German-speaking audience in Vienna.
International audiences nonwithstanding, it's just hard for many people to hear song lyrics, and a very common choice to make song lyrics simple, and hearing lyrics is critical for opera in a way it isn't if you're singing Goethe at a small salon concert.
The original point is it's silly to compare opera lyrics to spoken dialogue. Songs with belabored and repetitive lyrics can easily be interesting, spoken word with this property is banal.