Why is church attendance up in the U.S. but Christianity seems to be on the decline?
As in Isaiah's day, largely because there are blind preachers in powerless pulpits scratching the itching ears of people who want comfort over conviction and acceptance in the culture over the carrying of Christ’s cross.
That's my take.
10] For the LORD has poured out upon you
a spirit of deep sleep,
and has closed your eyes (the prophets),
and covered your heads (the seers).
 And the vision of all this has become to you like the words of a book that is sealed. When men give it to one who can read, saying, “Read this,” he says, “I cannot, for it is sealed.”  And when they give the book to one who cannot read, saying, “Read this,” he says, “I cannot read.”