In fact, a person thirty years old has heard very little good singing unless her family took her to church or to classical performances.

I don't fully agree. A person can hear what I consider to be good singing from good folk, old-fashioned pop, or even older country, or bluegrass, performers.

Wretched singing has become standard. When I shop or eat out I am forced to listen to some of the ugliest sounds I have ever heard - singing out of tune, singing through the nose, the gurgling of phlegm, shrieking, wailing. Many people today think that's what singing is.

That part, I do agree with.

Peter