I guess I'm a bit of a philistine myself. I'm interested in singing of all kinds. I have a recording called "De mi alma latina" (from my latin soul) by Placido Domingo that I enjoy very much.
I find this recording fascinating because it's true -- his musical soul is in these songs as it often isn't in his serious work. There is rubato all over the place. There is sliding.
He has a vast repertoire which he sings in the same mildly expressive, somewhat bland style. He is a fine musician and a great singing actor, to be sure, but he works no expressive miracles for me. Without the video I don't listen to him.
This is somewhat akin to blasphemy. In the opera world the man is virtually sanctified.
Practically everyone crossed over from somewhere. Placido came from the tradition of zarzuela in Mexico. Only a few, like Luciano and Cecilia, are singing in their native musical language.