Mrs. Buce offers a constrained maximization problem: you have a limited budget and you have to present both Gotterdamerung and Traviata. How do you allocate your money?
Her point: for Verdi, you've got to have singers, so in Traviata, you can skimp on the orchestra. But for Götterdämmerung, people don't expect to enjoy the singing anyway, as long (I would rephrase) as the orchestra is loud enough.
I see her point. On the other hand, there may also be a substitution problem. If your Violetta catches a cold, there probably a couple of dozen other Verdian sopranos who can make a plausible claim on the role. But for any Wagner role, is there ever any more than one person--anywhere in the world--who is right for the part?
You can surmise my preference here. I'm one of those who believe that a Wagner opera is one where you go at six o'clock and sit for three hours and check your watch and it's 6:20.