No, Not Exactly
Alex Ross takes heart, or something, from the fact that tenor Lawrence Brownlee got the idea of being an opera singer from the Three Tenors. I think he's missing the point. It's not that I object to drawing conclusions, even fuzzy ones, from a single data point; lacking sophisticated polling mechanisms, the most anecdotal evidence will do just fine for us thumb-suckers. It's that he's mixed up supply and demand.
No one has ever made any claims about the influence of the Three Tenors on the development of opera singers (indeed, I don't think anyone but Tony Tommasini is particularly concerned about that aspect of the operatic economy). The question is how to develop the audiences for opera, and whether Plácido and the boys have helped that process in any way. I don't see any reason to think they have, although we could always argue it over a few more times. But either way, Lawrence Brownlee's story doesn't add anything to that debate.