i've noticed that when operatic music appears in commercial or popular culture the singer is usually some unidentified person you'd prefer not to hear.
Fair observation. I wasn't thinking of the use of opera in high-quality films, where it's apt to be respected, but of more commercial uses.To be fair, I've noticed the opposite. I think of Callas in Philadelphia and The Iron Lady, Caruso in Woody Allen's Match Point (although recordings with less well known singers were also used in that film), Janowitz and Mathis in the Shawshank Redemption and Tebaldi and Bergonzi in Moonstruck. The film Quartet in which the Rigoletto quartet is central uses the recording by Sutherland, Pavarotti, Milnes and Tourangeau.
That said, when opera is used in commercials (and that's where we are most often to encounter it outside of classical music circles in everyday life), lesser known artists in presumably cheaper to license recordings are often heard.