As a second tiered member I'm told that I may compliment good answers. If that is so then congratulations APIRIL.
If members of this forum have been to Italy, as I assume many have then they must have seen an opera since they are presented almost every evening.
Admissions can be highbrow but there are $3.00 seats for the young people and those who can't afford the "orchestra". I attended a dozen or so on my wife and my last visit (she is Italian) and every night was a sell-out. Just jam-packed.
I looked carefully at the audience and the majority were 18-40 in age. As the opera progressed it was easy to see that the young people knew every line in the libretto (that's the script).
Ans when the finale came and the leading singers made those difficult or high notes those young people screamed with delight.
Bravo ! Bravo ! they shouted from every corner of the theater.
Then they hurled down bunches and bunches of flowers until the stage apron was filled. At the final curtain the lead female and male singers came forward, picked up ONE flower from the floor, faced the audience ands bowed deeply in appreciation.
THAT IS OPERA !
The secret is it would be terrible if you didn't know the script so we were told and given a "linretto" for each opera, the day or so before and we read the English translation of every line that was to be sung. Then wew read the plot of the opeera, often a love story but with intrigue, murder, dishonesty and virture all woben in to a really interesting story.
But in America, young people will not go to the trouble of getting a translation and reading the story. If they did they might enjoy Opera. It is just a different musical form.
But do young people like "The Nutcracker", "Beauty and Beast", "The Pirates of Penzance"? Some do and those same folks would probab;y take the trouble to learn the way to watch opera
So, the answr to the original question is Opera is NOT Highbrow in Europe. It is for the common folk there and the hoy poloy in America ! How sad !!