I can't post the whole talk because, while I had several pages written out, I also inserted a long section on the question of how Wagner should be sung right at the beginning, and that was delivered extemporaneously, based on some rough notes from my research.
I learned a few interesting things while putting the talk together, one of which I only realized fully in the middle of the talk itself.
I discussed something close to a dozen singers, all of whom were retired from staged opera by 1950 at the latest. Melchior's last stage performance was a Lohengrin in 1950 at the Met; Rudolf Bing gave him and Helen Traubel the boot that year. The circumstances remain, to me, a bit murky, and could have included a general house-cleaning, Bing's dislike of Wagner, Melchior's dislike of rehearsal, Melchior's age (he was 60 and not exactly a dashing figure at that point), and various other issues. In any event, Melchior concertized through the 50s and perhaps into the 60s; Traubel didn't sing much opera after that, as far as I know. The Corsican Cesar Vezzani retired as a result of ill health in 1948 and lived a few more years.
A few things really struck me.
Several of these tenors came from poor or working-class families and didn't have much formal education. Walter Widdop, the fine English tenor, left school at 12 to work in the mills, and didn't become a professional singer until age 30. Paul Franz and one of the other singers were railroad workers. Franz was also a late starter, again at age 30. Wealthy patrons played a role in the careers of several of the singers. So becoming an opera singer provided some economic and social mobility for these tenors.
Could that possibly happen today? We do not abound in wealthy people looking for poor singers to sponsor; since the 19th c. opera has been reframed, especially in the US, as an elite or aspirational art form, rather than an everyday form of entertainment. Youth who are thinking about music are far more likely to buy a guitar, which you can learn on your own, than to think about opera singing.
I was also struck by the trajectory of some of these careers. While Miguel Fleta burned out early and died young, and Isidoro Fagoaga fled the opera world under odd circumstances, the balance of the singers had long and distinguished careers of 25 to 40 years. That does not seem to be the norm these days, when 20 to 30 years is more typical. And these were singers in the most strenuous and difficult tenor repertory.
I was surprised by the fact that several made their debuts after just a couple of years of study, and several made their debuts at 25 or younger as Lohengrin. Few professional singers get on stage these days with so little formal study or in a helden role.
Also interesting: except for Melchior, who after a certain point sang Wagner 95% of the time, all of these singers sang a wide variety of German, French, and Italian music. The French tenors and the Russian Ivan Ershov had particularly wide repertories.
I had to wonder about at least one of the tracks I played. The Slezak recording of "Nothung! Nothung! Neidlisches Schwert!" has two serious flaws: significant blasting and distortion, and Slezak sings some obviously wrong notes. He was an enormously prolific recording artist. Why did this ever get released???
Lastly, Cesar Vezzani sang all over the French-speaking countries and North Africa, it seems, from the liner notes to the Marston sets, in houses I've never heard of. I would love to know if these houses had full opera seasons (like the Paris Opera or Opera Comique or Met) or whether he was singing at the equivalent of West Bay Opera and Festival Opera. Or was there just a much larger operatic ecology than now?